The public green

1. The changing concept of garden throughout history

Evolution

The word garden, of Indo-European origin, dates back to the meaning of enclosure, closed place.
The term indicates a protected space where it is possible to find shelter and relaxation. The first examples of gardens have very ancient origins: according to historical evidence, in the territories of Mesopotamia there were real green areas exploited as orchards and gardens dating back to the third millennium. Dating back to the second millennium instead, are the first Assyrian examples, in the double variant of public gardens and gardens belonging to royal palaces.

Often the space used as greenery took on a symbolic meaning, sometimes sacred, almost as if to represent earthly paradises rich in plant species with beneficial properties. Originally, the garden follows a precise structural scheme divided into functional areas, adorned with rows of trees and protected from the outside by a wall. It is a place of leisure and relaxation but at the same time it is used for the cultivation of fruit and vegetables and wine.

It is important to note how the shape of public gardens changes over time in close relation to the changes in the city. Such changes are dictated by social needs which in turn are caused by historical contingencies. While in ancient Greece the garden had little importance and served as a simple ornament of the most important city squares, in Rome the prata publica were green spaces indispensable for collective daily life. They were patches of woodland interspersed with avenues for walking where people met and spent their free time in company. Furthermore, the introduction of the architectural element in gardens is due to ancient Rome: the colonnade (peristyle), the pergola (periptero) and the temple (tholos) had specific functions and were framed by flowers, plants and trees.

As anticipated, it should not be forgotten that green space is modeled on the real needs of the time, as it constitutes an integral part of the urban fabric. For this reason, in the Middle Ages, the need for defense from external attacks forced the city to be delimited by walls and significantly reduced the spatial availability. This resulted in the placement of green spaces outside the walls and their use as lawns and tournament areas.  

In the Renaissance period, there was a real revolution in garden design: in relation to the rapidly expanding city, it was seen as a precious place that referred to the natural world. The art of gardens involved the most prominent architects of the time, who were committed to studying the shapes and placement of trees and shrubs in great detail.

Subsequently, the built element prevailed over the planted one, to return in the 600th century to vegetation occupying increasingly larger and no longer delimited spaces. Aristocratic villas opened the gates of sumptuous private gardens, laying the foundations for the concept of the public garden open to all. The 700th century was instead characterised by the introduction of a first classification of urban green space divided into enclosed gardens, avenues for walking and public gardens. The latter developed greatly during the 800th century, becoming a true social phenomenon in England where the population was growing rapidly. The less well-off segment of citizens who did not have a private garden thus had the opportunity to spend some free time in contact with nature. The phenomenon quickly gained the approval of the poorer social classes, thanks to whom the professional figure of the landscape architect emerged. The first public parks in France and England consisted of rest areas and walking areas equipped with street furniture; the model soon spread throughout Europe, arriving at the present day with its current features.

Function and structure

Closely linked to the characteristics of society, the function of the garden over time is directly reflected in its structure. Throughout history, some functions have followed one another aimed at satisfying specific needs: providing shade, shelter and relaxation areas, expressing magnificence and splendor and also cultivating plant species and medicinal herbs. 

In all cases, the garden is seen as a space to be cared for and preserved, a place of peace capable of calming the spirits from daily difficulties.
It often assumed an ascetic meaning, seen as a place of meditation or was an element representing the power of noble families and houses (private gardens). Furthermore, for a long time the green space provided the possibility of studying and knowing the plant species that composed it, becoming a useful means for the knowledge of botany.

The civilizations that have succeeded one another throughout history have distinguished themselves by considering gardens with greater or lesser importance and by dedicating more or less profound attention to them from the point of view of structural design.
In ancient Greece, the term garden has sacred connotations; the basis is the concept of gratitude for the divinity that contributes to the fertility of the land. Usually enclosed by walls, they had a geometric layout and were divided according to the different uses: animal breeding, rows of fruit trees, an area intended for worship.
For the Romans, however, the garden has a social and ornamental value, a refuge from daily toil and a place full of religious meaning, a true paradise on earth. These are spaces, the creation of which is promoted for the people by the rich Patricians and later by the Emperors; fenced and bordered by porticoes, they had a complex structure and rich in fountains, statues, terraces, stone benches and small temples. 

During the Middle Ages, historical events caused a strong change in the structure of the garden; the growing need for defense led to an ever decreasing opening towards the outside and the open space used for greenery was also affected by this. The so-called “Hortus conclusus” was born, closed by four walls, inside the monasteries, it housed a fountain in the center and the remaining land was used for the cultivation of medicinal plants and orchards. The situation was very different during the Renaissance when the garden lost all functional value to become a space intended for leisure and pleasure.

The introduction of fixed parameters in the spatial organization generates a very precise design of the territory. The artificial element prevails over the natural one, rigor and symmetry are the basis of the overall scheme. Water becomes a fundamental element: fountains, jets, water games make the garden an almost theatrical environment.
In the following period, society experiences profound transformations and the city of the 800th century leaves ample space for the use of different elements. For this reason, there is no defined model of garden but a mix of styles and connotations from the past prevails.

New social demand

Between the end of the 800th and the beginning of the 900th century, the rapid growth of cities and the construction of many buildings caused the growing need to introduce urban green spaces open to the public. Soon, from the larger cities, parks also spread to towns and villages where the demand for areas for collective use was increasing. Over time, these spaces have taken on an increasingly specific functionalization, distinguishing themselves into areas dedicated to leisure, rest, sport and play.

Today there is a constant need for greenery in the city, not only aimed at the well-being of the individual but also at the ecological balance of the entire urban structure. In a changing city context, where pollution represents a serious threat to the psycho-physical comfort of the individual, green areas characterize an indispensable element of social connection and a useful improvement tool. Furthermore, due to the progressive standardization of the urban aspect, citizens have gradually lost the original sense of belonging to a community. To overcome this problem, collective public spaces are used and specifically neighborhood parks and gardens, capable of regenerating and creating sociality. They can give a specific identity to the territory, promote the psycho-physical comfort of the individual and increase the liveability of the environment.

The need to restore a differentiated image of the city and of places intended for the community, combined with the needs of a much more varied society than in the past, leads to a concept of greenery less bound to pre-established schemes. Unlike some past historical periods, today free forms that follow the morphological trend of the land and that adapt to the reality in which they are located are usually preferred. An extensive type of vegetation arrangement prevails, which guarantees easier use of the spaces, low construction costs and simple maintenance. Native species are used more, distributed over the entire surface according to the need for shade or sunlight and not according to pre-established geometries and designs. The aim is to satisfy not only aesthetic needs but also and above all functional ones. The area must be designed according to the properties of the context in which it is located and to which it must integrate perfectly; the internal and external paths of the area must be perfectly connected to guarantee the free flow of people.     

2. Public greenery in urban planning

In the current panorama, we can find a renewed interest in the theme of landscape and urban greenery. This factor is caused by the growing collective sensitivity for the environment and by the awareness of the worrying current situation that sees the territory we inhabit put in serious danger. This is how environmental movements and associations for the protection of the environment are making their way, demonstrating the need for constantly updated laws on landscape plans.
Despite these first steps towards greater collective participation, today territorial planning at the municipal level and legislation do not pay due attention to urban greenery and its protection. In step with the international political commitment to sustainability, Italy introduced a law in 2013 regarding public greenery and its protection – law 14 January 2013, n.10. However, these are often premises that are not considered in practice or are applied sporadically and not at a global level.
It is necessary to address this issue in a systematic manner using specific governance tools through which to implement planning and correct management choices.
Although there are numerous differences at the municipal level between Italian cities, there are three tools used by the administration to regulate urban territories:

Analysis and monitoring tool: green census
Section in which public and private greenery present in the urban and peri-urban territory are analyzed. A classification of the main species and their relative distribution identified through a map survey is also reported.

Regulatory instrument: green regulation
It concerns the rules relating to the design, insertion and future management of greenery. 
The plant types that can be used depending on the context and needs are taken into consideration.

Strategic Planning Tool: urban green plan
Manages the implementation methods of interventions relating to public greenery.
Added to these are the Green Monitoring and Management Plan, which varies from year to year depending on municipal needs and is aimed at guaranteeing citizens satisfactory services and the Green Information System.

The Urban Green Plan

The Urban Green Plan is the tool that determines the set of interventions aimed at promoting the qualitative and quantitative development of urban greenery and deals with its management and maintenance measured with respect to the specific context.
If applied correctly, it can bring many environmental benefits, reducing the impact of urban activity on the territory, in order to restore the green structure desired by the citizens themselves. The Urban Green Plan is an integral part of the strategic territorial planning and is composed of the following sections:

• Cognitive framework
• Address plan
• Technical implementation standards

Too often the Green Plan is mistakenly considered a sector tool in itself, when in fact it is a complementary document to the entire urban planning. In fact, it is useful for knowing, preventing and conserving the territory being planned. Furthermore, the Urban Green Plan should involve the population in the design choices and decision-making processes that concern the territories they inhabit. Differently from other European countries, in Italy landscape planning is not entrusted to the city council but is managed at the provincial level with the Provincial Coordination Territorial Plans. It would be good practice instead to establish the General Regulatory Plan (PRG) taking into account the environmental structure, thus coordinating the various aspects in a single tool considered at a global level that regulates the buildings and infrastructures on the basis of landscape planning. This disorderly and communication-free structure does not favor a planning conducted in accordance with conscience and respect for the environment in the country. In fact, according to a recent analysis conducted by ISPRA (Higher Institute for Environmental Protection and Research), despite the growing interest in sustainable development and environmental protection, there are few bodies in Italy that have prepared the Urban Green Plan. In fact, there are only 7 cities that have applied the principles of this tool: Milan, Venice, Bologna, Parma, Prato, Reggio Calabria and Cagliari.

This bad habit generates numerous management and maintenance problems in the cities we live in. For example, the absence or scarcity of green areas integrated into the built environment, the low quality of the ecosystem, gardens and parks that are rarely visited and therefore unsafe.
It is therefore necessary to act at all scales, keeping a firm hold on a plan that considers the city in all its parts and especially the greenery, an indispensable element of connection of the entire urban fabric.

Green classification

Policies relating to urban greenery, as already mentioned, often prove to be lacking also due to the lack of information on green spaces within cities. The direct consequence is the collective misinformation on the value of this unfortunately underestimated resource: it is necessary to introduce a global information system, accessible to all, capable of monitoring and managing this collective heritage.                                                                               

To this end, a typological classification of urban green areas has been drawn up:

NEIGHBORHOOD GREEN SPACES → these include public gardens, those pertaining to residences, play areas, and green areas serving commercial and production areas.

GREEN SPACES AT MUNICIPAL LEVEL → this includes green areas intended for sports facilities of urban importance, medium-sized public parks, wooded areas or riverside areas.

CONNECTIVE ELEMENTS FOR THE CREATION OF NETWORKS OF GREEN SPACES → cycle paths, tree-lined avenues, pedestrian areas.

The typological classification must take into account all the characteristics of the spaces it considers, including their dimensions.
In this regard, the division according to size classes includes:

• SMALL SPACES → gardens under 1.500 mXNUMX
• MEDIUM-SMALL SPACES → gardens between 1.500 m2 and 5.000 mXNUMX
• MEDIUM – LARGE SPACES → gardens between 5.000 m10.000 and XNUMX mXNUMX
• LARGE SPACES → parks larger than 10.000 mXNUMX

As can be seen, the transition from garden to park occurs over 10.000 m2 of surface. In the analysis and management of urban greenery, reference is made to some indicators capable of signaling critical situations or poor use. They are functionality, services and furnishings, safety, aesthetic quality, pressure factors from the context and maintenance.
From a functional point of view, it is preferable to organize the area into equipped zones designed for a specific use so as to encourage socialization between different users and prevent possible conflict phenomena.
It will be optimal to fence the area intended for children's play and the one intended for dogs, also to ensure the safety of all users. The furniture will be of fundamental importance and necessary for the differentiation of use: comfortable seats and recreational tables for the elderly, parking for bicycles, toilets and bins for waste collection. Furthermore, all spaces must be easily accessible: entrances and exits clearly visible and tangible, paths free of obstacles and no architectural barriers.  

It is essential that during the design phase the functional aspect is taken into account, but also that relating to aesthetic quality, as this constitutes an important added value that encourages people to frequent the area more. The influx of people thus makes the frequented spaces more lively and gives a sense of greater security. Although an accurate design that takes into account the factors mentioned above is the basis for the creation of successful collective spaces, there are some elements that can sometimes compromise their balance.
These are the factors of external pressure and the management of spaces over time. For example, the presence of heavily trafficked roads characterizes the greatest threat in terms of noise and air pollution. The proximity of railways also constitutes a cause of strong disturbance due to the noise produced.

As far as maintenance is concerned, it is a clear indicator of the physical-environmental quality of the green area; the care of the grass, sometimes very demanding, should be a fundamental prerogative in order to keep the surface continuous and free of dirt areas. The paths must be clean and free of obstacles, the furniture efficient and in good condition. It is also important to keep the area clean, there must be no waste or dog excrement. Naturally, the civic sense of the users is a determining element for the quality of collective spaces, too often prey to carelessness and a lack of sense of belonging.

FUNCTION OF GREEN

The urban environment lends itself to welcoming green spaces as active elements with various functions; they fulfill the role of social incubators for sports and leisure activities and improve the environmental and aesthetic conditions of the city. For this reason, today urban greenery has assumed a significant importance, changing its function from a mere residual element to a necessary actor for the community. 
Below are listed some of the functions that urban greenery plays, which contribute to the improvement of the psycho-physical conditions of the individual who lives in the city and lead to the renaturalization of the city environment.

Ecological function

As is well known, there is an excess of carbon dioxide in cities caused by vehicle engines, domestic activities and the action of industrial and residential plants.  
Through the process of photosynthesis, plants are able to capture and retain dust suspended in the atmosphere, subsequently releasing oxygen. Even the grassy expanses of meadows and green land perform a purifying function since they are positioned at the same height as car exhaust fumes. The polluting particles present in atmospheric dust are captured by leaves that have different capacities depending on the size and characteristics of the leaves themselves. Trees retain a much higher quantity of dust than grass, which in turn intercepts a quantity six times higher than smooth surfaces. Furthermore, plant species are able to contribute to correct thermal regulation: the green masses prevent excessive heating of the soil by blocking the evaporation of the water contained within it. This is how a tree cools the environment with the capacity equal to that of five medium-power air conditioners; this is equivalent to a 40% saving in economic and energy terms for summer thermal conditioning.

Acoustic function

Noise is considered a significant pollution factor because it causes significant psycho-physical damage to individuals. The urban context is increasingly characterized by the presence of numerous sources of noise and for this reason green areas must contribute to the attenuation of the resulting damage. To this end, noise screens are inserted in collective green areas that act through absorption, reflection or deviation of sound energy. Another method is that of sound attenuation, obtained by lengthening the path of the sound waves from the source to the reception point.                     
Plant barriers act with more or less intensity depending on the characteristics of the plants used: species with foliage also present in the lower part of the trunk and evergreens are perfect to guarantee protection throughout the year. The protective result also varies depending on the thickness and height of the screen, in fact the most advantageous solution is characterized by tall hedges with a thickness of at least 5 meters. Green barriers are also excellent solutions for visual isolation.

Hygienic function

Since ancient times it has been demonstrated that the presence of the green element in the anthropized environment improves the living conditions of the individual. In fact, vegetation would help maintain a balance from the point of view of the hygiene of the places and consequently of the well-being of the person.

Social function

From a recreational point of view, green spaces are perfect for the correct growth of children who can play and interact in the open air. Healthy areas protected from the rest of the city are not only useful for children but also for adults and the elderly who can meet here, play sports and rest in their free time. Furthermore, the therapeutic function of the green element is also recognized since in an environment rich in vegetation, man is "lightened" from the overload of thoughts and daily worries.
In fact, it has been demonstrated that at the sight of certain plant species, blood pressure and muscle tension in humans decrease.

Aesthetic function

Although the current trend considers the functional aspect of equipped green areas as the main one, aesthetics is not an element to be overlooked. In addition to the improvement of the entire urban environment, a well-designed space from a formal point of view ensures differentiation from the monotony of buildings and streets.
Furthermore, areas rich in vegetation improve views and views of the city, the potential of which is sometimes not even taken into consideration.

3. The garden and the public park

From the early 900s to the present day, urban green spaces have taken on an increasingly important role  
most important for citizens and the neighborhood park and garden are the most widespread example of this. 
Both are characterized by an area inserted in the urban context, of variable dimensions and which hosts vegetation and areas used for specific functions.

Differences and similarities

Unlike past eras in which people felt forced to follow rigid formal schemes, today green areas are conceived as a mix that blends the formal and functional aspects.
In the context of the contemporary urban landscape, parks and public gardens play a fundamental role in the bond between man and the now almost lost natural element.
Both are called to respond to similar needs (play, leisure, recreational, sports), must be easily accessible from the entire urban fabric and must guarantee easy accessibility for everyone. However, some aspects can be found that differentiate the urban park from the neighborhood garden, first of all the size: we start talking about an urban park starting from 10.000 m2 of surface, while below this value we talk about a garden.

The urban park, very large, is often located on the outskirts of the city and serves a hygienic-recreational function. Thanks to its generous dimensions, many activities can be placed there; these are real functional areas structured according to standard schemes and rules. The lawn solution is the predominant one because it is easy to maintain, and is intended to highlight the vastness of the whole.                                                                                       
If the park is located in areas affected by suburban expansion, there could be areas used for vegetable gardens and spaces that recreate specific natural habitats, in order to develop and protect animal species that contribute to the ecosystem balance.

Parks can be classified into:

• URBAN PARKS → medium size, formal appearance, recreational activities
• METROPOLITAN PARKS → large size, large influx of users
• METROPOLITAN BELT PARKS → ecological protection, agricultural activities

Generally speaking, it can be noted that a greater presence of the plant component corresponds to a lower intensity of design of the architectural component. 
As for neighborhood gardens, these are small green spaces, introduced in the first half of the 900th century, which soon spread like wildfire throughout the urban fabric. Today, they fulfill an important social function because they can be used daily by the neighborhood's residents who consider them a point of reference and meeting place. The design of these spaces requires a lot of attention because an intense flow of people in limited spaces is expected.                                           
Below are some small design tips that are useful to users: correct placement of shrubs ensures the alternation of shaded and sunny areas; the choice of plant species can be varied but must imply little maintenance; native types are to be preferred; the alternation of green areas with paved and equipped spaces guarantees the easy carrying out of recreational and sporting activities and moments of rest; the absence of architectural barriers must be guaranteed unconditionally from the early design stages, so as to allow access also to the disabled.

As for the neighborhood garden project, it must provide more than anything else, the correct integration with the context. The choice of flora, for example, must be made by studying the local species: a scheme of native typologies that replicate the most widespread biomes in the specific territory is necessary. Thanks to the presence of shrubs and vegetation, the neighborhood garden reduces the effects of the "heat island" typical of the urban environment, also decreasing the action of pollutants. Furthermore, since the activities carried out outdoors are closely linked to the daily rhythms and to the life that takes place inside the buildings, a close relationship between the design of the gardens and the surrounding buildings is necessary.
From a social point of view, these are green areas that can be reached mostly on foot by the elderly and children, closely integrated into the residential fabric. The neighborhood garden, unlike the park, due to its small size and its ability to bring people together, constitutes a point of reference for the inhabitants of a specific territory. Thanks to it, citizens feel part of a community (a feeling that is often too faded in contemporary urban environments) and develop the ability to interact and socialize with each other. 

Three examples from Milan

Sempione Park, Milan

It is an urban park located in the area adjacent to the Sforza Castle in the city of Milan. Dating back to 1893, it covers an area of ​​386 m000 and is an important example of a Romantic English-style park. With its irregular layout, Parco Sempione contrasts with the very orderly city plan. Entirely fenced, it contains many plant species and a differentiation of spaces dedicated to play, sports, recreational activities and animals. Today the large spaces that make up this vast green area are used for important Milanese events and demonstrations. 

Forlanini Park, Milan

The park was inaugurated in 1970 and with a surface area of ​​750 m000 is located in front of the Milan Linate airport. It is a metropolitan park that still retains, in part, agricultural activities. Completely without a fence, today it is in continuous expansion and transformation also thanks to the contribution of Associations and citizens who are committed to its management on a daily basis. Since it occupies a very large area, there are various plant species and local fauna that distinguish it.

Southern Agricultural Regional Park, Milan

This is a park in the Lombardy Region that includes part of the territory of Milan and the municipalities to the south, east and west. Established in 1990, it was created to protect the landscape and provide the territory with a large green lung. The total surface area measures 46 ha and the landscape is typical of the Po Valley consisting of crops, some wooded areas and numerous waterways (Southern Lambro, Naviglio Grande and Pavese). 
As for the fauna, it is concentrated above all in the natural areas of the park while the largest percentage of vegetation is distributed along the banks of the rivers.

The neighborhood garden

Unlike in the past, today, public greenery is no longer considered a negligible element aimed at filling simple residual spaces but constitutes an aspect of primary importance that requires a real design process. It is therefore good practice to follow some rules so that the public garden project is effective in concrete reality.

PARAMETERS FOR CORRECT DESIGN

At the base of each intervention, it is necessary to conduct careful research on the specific context; it is essential to know the characteristics of the environment in which you operate by evaluating its constraints and potential. For example, in the case of an unpleasant external area, the garden may take on a closed shape, aimed at isolating the green area from the context. If, on the other hand, there are interesting urban views, an open or targeted composition is preferable, in order to direct attention towards the most valuable points. In any case, the garden must be an integral part of the urban fabric and guarantee coherence between the built environment and the natural habitat. Below are listed some of the useful parameters to ensure design harmony in relation to the context.

Design unit
It involves choosing an element that functions as a matrix for everything that will make up the neighborhood green space. In some cases, it can be the lawn in relation to the shrubs or a plant species that predominates over the others that, following one another, restore an appreciable overall harmony.

Proportions and division of spaces
In order to obtain a harmonious compositional whole, it is necessary, once the design unit has been defined, to maintain the proportions. The volumetric shapes of shrubs and built elements must be calibrated so as not to differ from the expanded shapes of lawns, paths and water elements. Furthermore, the right balance must be created between diffused volumes and defined volumes in terms of plants and shrubs; the former guarantee lightness thanks to the mobile foliage, the latter follow a precise and more formal design.

Graduality
Each element that makes up a green area should follow a precise gradation aimed at ensuring a pleasant overall harmony. The correct progression between masses and volumes consists in the succession of different vegetation levels that manifest themselves with increasing heights that go from the herbaceous level to the shrubby one and finally to the arboreal one.

Choice of colours
The choice of color during the design phase is an element of fundamental importance. 
Today, the wide range of products and colored finishes allows you to achieve optimal results from an aesthetic point of view, provided you choose consciously. 
Knowledge of the fundamentals of color theory (complementarity, contrast, harmony) is useful for design purposes to obtain pleasing views and scenes.

Choice of plants
Urban greenery is selected based on the destination, shape and use of the green area for which it is intended. Given that greenery is divided into furnishing greenery and functional greenery, there are some parameters that can guide the choice of specific species.               
One of the first elements to consider is the geomorphological conformation of the soil on which you are working: depth, humidity, slope, exposure of the land will be determining elements.  
Next come the climatic, environmental, urban fabric and aesthetic aspects. The latter vary depending on the characteristics of the plant species, such as foliage, flowers and fruits.      

The garden as a pleasant place, accessible to all For a place to be defined as pleasant, some qualitative requirements must be satisfied, which are fundamental for comfortable use.
In the case of municipal green areas, these elements are represented by four indicators: accessibility of the place, activities carried out, comfort and social value of the area.

Accessibility
A fundamental prerequisite for all public areas is that they are clearly visible and easily accessible to all. Properly connected by public transport, they must also be noticed from medium-high distances and have space for parking cars. Furthermore, it is essential that the internal spaces are accessible, easy to use and free of architectural barriers.

Comfort and aesthetics
Safety and hygiene are the guarantors of comfort and well-being in public areas. The spaces must be usable and equipped with seats to be used when needed; in fact, the lack of street furniture in public green areas is often the main cause of their malfunction. 

Activities
They give uniqueness to the place making it desirable by the people who return there. In the absence of attractive poles or activities carried out, in fact, the place remains deserted.

sociability
Social activity makes the space more attractive and fosters a sense of belonging among citizens to a specific area.
Too often these good design practices are ignored and the direct consequence is the non-functionality of the space. In fact, many places are designed more to be looked at than frequented every day. Often, in fact, there is a lack of attractive fulcrums, the entrances are hidden and uninviting and uncultivated vegetation obstructs the passages. 
The internal and external paths to the green area should be conceived in close relation to the context, remembering that the flow of people is directly proportional to the accessibility and visibility of the space.

Removal of architectural barriers
Since proper design is aimed at the free and easy use of assets, the total absence of all those elements that limit or hinder their enjoyment is necessary.
These are the so-called architectural barriers that are often the subject of numerous debates. Everyone must have equal opportunities regardless of their level of motor and sensory ability and to this end, Presidential Decree 503/1996 applies, a decree concerning the rules relating to the removal of architectural barriers in buildings, areas and public services.
The design criteria must be based on the principles of accessibility, visitability and adaptability; in fact, the disabled person must be able to use and visit the public place independently without difficulty. 

The elements considered by the current legislation are analysed below. 

ROUTES
Optimal when located on a flat surface, the paths must have a minimum width of 0,90 m and every 10 m in length have wider spaces that allow wheelchairs to be turned around.
The maximum permitted slope is 5-8%, horizontal parking spaces are required every 10 m and there must be no obstacles. In the design phase, the optimal width to take into account for the creation of easy paths for everyone is 1,5/2,00 m. 

RAMPS
The minimum width of the ramps must be 1,5 m to allow access for two people in wheelchairs if they cross. In addition, there must always be a horizontal shelf measuring 1,5 x 1,5 m every 10 m to allow for changes in direction.
The ramp must have a regular shape and a handrail of 0,90-1 m high must be inserted on both sides. The maximum slope of the ramps is 8%.
It is also essential to have a material signal at floor level for the start and end of the ramp that can be perceived by the visually impaired.

FLOORING

From the early design stages, it is of fundamental importance to consider the material-structural conformation of the external flooring of common areas and green spaces. It must be designed to withstand the overloads expected over time and the surface must be non-slip. The paths must be easily identifiable, sometimes even by resorting to chromatic or material differentiation, as long as it does not cause disruptions or differences in level. The latter are permitted up to a maximum height of 2,5 cm and if it is greater, connecting ramps with a maximum gradient of 15% must be inserted. 

SEGNALETICS

Informative signage is optimal in common green areas and allows users to understand if special solutions have been adopted that facilitate use by disabled people.            
For the blind, it is necessary to insert audible signs or panels written in Braille to help them orient themselves and understand any dangerous situations.

STREET FURNITURE

As for the furniture placed in green areas, it must be used by everyone without discrimination. The components must be safe, comfortable, accessible, durable over time and pleasing to the eye.  

The composition of the garden

Soil
The design of the public green space starts from the analysis of the context and the spatial and natural conformation of the place. The quality and healthiness of the area depend on many factors, first of all the soil.
The landscape is constantly changing in relation to the natural forces of atmospheric agents and climate change. For this reason, it is necessary to adopt the best solutions to optimize soil performance, avoiding its deterioration. It is therefore clear that one of the preliminary needs is to preserve the quality of the soil in relation to the functions that will be placed there. To do this, it is essential to maintain the maximum level of permeability of the soil through drainage systems. Furthermore, it is necessary to pay maximum attention to preserving the fertility of the soil and its biological component, since the area of ​​intervention for the creation of the public garden often has heterogeneous and variable soils. In fact, it may happen that the organic component of the soil is very low; in this case, we proceed with an intervention to correct the substrate. It is essential to be aware that the soil is the basic element on which the actual quality of everything that makes up the green area on the surface depends and for this reason one of the primary objectives is to maintain the right natural balance of the soil. 
The stratification must guarantee permeability and must be made up of overlapping materials that blend with the nature of the place. An important factor to consider is also the management of rainwater runoff on paved and grassed soils. Through specific channels, the water is directed towards the infiltration areas or towards the centralized disposal network, guaranteeing the water cycle. 

Accesses and passages
Within the public green area, the accesses and paths are an important element for the comfortable use of the user. Designed to be easily accessible and accessible to all, they are made of materials capable of withstanding pedestrian and bicycle traffic. There must be a direct connection between the internal and external paths in order to allow continuity between the green area and the relevant lot and guarantee the greatest possible flow of people from the neighborhood who go to the garden.  
As for the materials used in the construction of paths and walkways, they must be comfortable and durable over time.

On the surface, the use of permeable materials, such as gravel, avoids the use of specific rainwater management devices, significantly reducing the overall costs of the project. Furthermore, the choice of materials is connected to the expected flow of users, climatic conditions, future maintenance and the diversified use of the area. It is interesting to understand how the routes are modelled on the needs of the user: movement and needs are determining factors. The common tendency is to move along a route towards an objective, identifying intermediate points (stops) and avoiding obstacles and adverse situations. Depending on the route, it is then necessary to study the typical section and the ground in order to guarantee the safety of the users. For example, the pavements of pedestrian and cycle paths must not be too smooth or too rough and the different speed of movement of cyclists and pedestrians will imply the use of different materials.

Today, the choice of material to be used is made based on the requirements of color, texture and consistency; furthermore, industrial processes allow artificial materials to obtain a yield very similar to the natural one, enjoying benefits from an economic and maintenance point of view. Furthermore, in recent years, the material used in the paths within public green areas has partly replaced the function of indicating the way to users, once fulfilled by vertical signs. Changes in color and texture are used to distinguish pedestrian areas from cycle areas, to signal obstacles or to give important information even to those with physical and perception limitations. 
Industrial progress thus assigns a multifunctional role to elements that until recently they did not have. 

Rest areas
Too often the failure of many public places and common spaces is caused by the total absence of rest and seating elements. The inclusion of benches and support surfaces makes the use of paths more pleasant and comfortable. In fact, the positioning of this type of component must guarantee availability to users at specific time intervals (one seat every 5-10 minutes of walking). The integrated design of paths and rest areas must take into account the speed of travel of the user (considering the lower speed of pedestrians) and the slope of the land on which it is being worked on. In fact, in areas with a greater slope, where the walking speed is lower, the seats will be placed at a shorter distance from each other.                                  
The function of the rest area is not negligible, seen as a place where you can find relaxation and refreshment or where you can socialize. To this end, it is important to connect the seating element to the context and to the possible insertion of tree species specifically for this purpose, to guarantee shade and rest areas especially during the summer season.  

Lighting
The design aspect regarding the lighting of places is necessary in order to enjoy them also in the evening and at night. It determines the characteristics of the space because it is able to highlight or on the contrary obscure specific elements. 
As for public places, the lighting project requires particular attention and versatility, imposing the use of resistant materials suitable for intense and external use. In this case, the devices can be fewer in number but must have a greater intensity in order to guarantee a good level of safety for users throughout the night.

The design process includes a preliminary analysis of the site's characteristics in relation to the context in which it is located; at a later stage it is essential to know the needs of the users. At this stage it is important to consider the quality of natural light, which varies depending on exposure and the time of year. Among the needs to be satisfied, first of all, safety allows you to walk through the area in peace even in the less visited spaces and in the perimeter ones. This is followed by accessibility for everyone and the relative flows that will establish the different levels of lighting. Only at a later stage will the lighting equipment be chosen and the technical parameters and performance verified. In the case of public greenery, the application of these principles will concern the lighting of: vegetation, paths, bodies of water. 

VEGETATION LIGHTING
In this case, the direction of the light beam, the location of the light fixtures and the qualitative and quantitative aspect of the light must be considered. Depending on whether the light is from below, above or from the side, completely different final effects will be obtained; the light from above reproduces a result similar to that of natural light, shading the lower edge of the foliage. The light from below or from the side, on the other hand, creates a completely different image, emphasizing the texture and shape of the vegetation. Specifically, trees react differently in relation to the position of the fixtures chosen based on the physical conformation of the same shrub. The general rule involves shielding the light source in order to avoid dazzling the observer. 

PATH LIGHTING 
The paths inside the common green area can be pedestrian or cycle paths. The lighting of the former varies in relation to the expected flows of people depending on whether they are paths, paths, avenues, sidewalks and large walking avenues. Another factor that influences the design choices is the function performed by the path. Usually the paths require devices with limited intensity and positioned low down while the pedestrian avenues subject to denser flows, require powerful systems with elements placed from above and screened so as not to blind the users. The lighting system of parks and gardens must be functional and must not lead users to divert their attention from the elements that make up the landscape (trees, furniture, sculptures). 
It is preferable that the light intensity of the path is constant and free of dark or over-lit areas and that the luminance levels between paths and surrounding areas are as homogeneous as possible.

WATER LIGHTING
In the event that the garden presents glimpses enriched by bodies of water, it is essential to artificially illuminate this important resource. The designer is faced with the dual choice of illuminating the body from the outside or inserting underwater devices. What is necessary to keep in mind is that light has some physical properties in contact with water. For example, given that moving water incorporates air inside it, when the light hits it it interacts producing air bubbles that give the water a shiny appearance. The creation of luminescent effects sometimes takes on great importance, becoming a real attraction that gives the area added value. 

Functional areas
We have previously spoken of multifunctional gardens, equipped with areas dedicated to specific uses. 
This is how, depending on the extension of the land for public use and the constraints of the area, useful areas are recreated not only from an environmental but also a social point of view. 
These are places of leisure, relaxation, and sport, where users of different social backgrounds and ages have the opportunity to meet and generate that precious exchange that is too often lacking in the urban scenario.
The most common uses within neighborhood gardens are described below.  

PLAY AREA
The playground is an important area dedicated to recreational activities of children and minors. Sometimes it is delimited by physical boundaries especially for safety reasons. 
The design of these spaces must be carried out with responsibility and attention, since it constitutes a recreational and educational scenario for a growing user base.
We often proceed in relation to the age group of children who have different types of needs:

• 0-3 years – grass surfaces or shock-absorbent flooring for crawling and moving freely, fenced playpens. It is useful to include seats for adults who have custody of them. 
  15 mXNUMX are calculated per child. 
• 3-9 years – grass surfaces and soft and hard flooring depending on use. 
  Play trails, areas of different levels to stimulate motor activity, recreational equipment (slides, skill passages, tunnels).
  25 mXNUMX are calculated per child. 
• 9-14 years – grassy fields for sports activities. Equipped paths, skating rinks and skate slides. Sports equipment (equipped walls and climbing walls). 
  60 mXNUMX per child are calculated even if in a smaller area, typical of a neighborhood garden, the value is lower.

Thanks to the presence on the market of a wide range of play materials and equipment, play areas within gardens could be very varied. 
However, in the design phase the choice often falls on classic serial models that favor the aspect of safety and simple maintenance, sometimes to the detriment of aesthetics. 
In a few cases, however, more innovative and creative play solutions are used in order to obtain a strong figurative impact. These are structures that reproduce forms with a strong evocative power for the child and that refer to the world of fairy tales. 

Although in Italy there is no real legislation regarding the safety of play structures, the design of these areas is approached with the aim of stimulating children to creativity, movement and sociability, always ensuring the safety and security of the user.

SPORTS AREA
In the case of the neighborhood garden, given its relatively small size, the sports area will offer a limited choice of services, if compared to that of the significantly larger urban parks. In the design of these spaces, great importance is given to the physical conformation of the grass that constitutes the playing fields.
It is important to consider the aspects regarding the compositional mix, processing and maintenance of the field. Since the ground will be subject to high wear, it is preferable to choose solutions composed of aggregates and membranes capable of withstanding heavy loads and stresses. In most cases, there are one or maximum two functional spaces dedicated to sports: basketball court, soccer field, tennis court, skating rink and skate ramp. In fact, based on the space availability, the offer will be more or less extensive.
Like other functional areas, the sports area is also designed to ensure safety and comfort for the user.

AREA FOR SENIORS
Although the elderly population is constantly increasing and more than any other requires protection and spaces for free time, in the Italian panorama the issue of green areas experienced by the elderly is still a topic little discussed. Often these spaces are not designed based on the real needs of this segment of users and the direct consequence is the sense of inadequacy that the users themselves feel. Poor maintenance causes material damage but also and above all psychological, for example when an elderly person finds himself walking on paths that are uneven or without seats. It is therefore essential that public areas become places of social integration and welcome different age groups who can thus share the same spaces.

In this regard, the neighborhood garden is the ideal solution for the less young people because it is easily reachable on foot and often located close to home. It is essential that the paths that connect the green space to the rest of the city are as stable as possible, non-slippery, compact and at least 0,90 m wide. In addition, rest areas must be included to allow rest partly in the shade. 

In any case, entrances, furnishings and internal paths must be easily accessible and completely safe. A determining factor for the success of this type of area is to recreate environments that are as familiar as possible where the user can feel protected and at ease. 
Some optimal solutions are characterized by the presence of shelters, gazebos, chairs, tables and small spaces dedicated to the game of bowls and similar sports. 

Functional and furnishing elements
The composition of the neighborhood garden is determined by countless elements that must necessarily be placed in harmony with each other and with the environment that welcomes them. 
These are units that can be fixed or mobile but which in any case must be durable over time and functional for the users who visit the area.                                    
In addition to furniture and equipment dedicated to particular functions, in collective green spaces we often find structures inserted to overcome particular situations of discomfort. An example of this is the stairs that, inserted in correspondence with significant differences in level, must ensure stability and ease of use of the spaces. The tread of the stairs must never be less than 28 cm in width, while the riser must not exceed 16 cm in height. Furthermore, the presence of a parapet along the entire length of the stairs is mandatory.

The second, but no less important, means to overcome any differences in level present in the outdoor area is characterized by ramps. Usable also and above all by the disabled, they must respect maximum slopes and for this reason they are a little more cumbersome in extension. Finally there are the walls and fences, fundamental in green areas to define spaces, separate any functions and screen views. 

In terms of furnishing for public gardens, today the market offers various products specifically designed to be used frequently and intensely but to last over time. These are mostly mass-produced objects where utility and safety prevail over aesthetics and originality. Like functional elements, furnishing elements must also be chosen in order to recreate a unitary composition and overall harmony. 

REST AREAS
Unlike the past, when the tendency was to place seats in quiet, intimate spaces to encourage individual relaxation, today the vision of the rest area as an opportunity for meeting, exchange and conversation has established itself. The design of rest areas and the placement of seats cannot be left to chance: it is preferable to place them near avenues and attractive hubs to allow a quick visual connection with other people or with elements that are pleasing to the eye. The ideal would be to guarantee users the possibility of choosing between shaded, semi-shaded and sunny rest. It is essential to take into account the importance of the choice of furnishing components, in order to achieve a good aesthetic result. 

The functionality and comfort of the seat are guidelines: for an adult the seat height must be around 45 cm while the seat must be 50 cm deep. If the bench is located in a grassy area, a light paving or protection from the grass is necessary in correspondence with the support of the feet. Today, when choosing, we often opt for modular and sectional systems that allow for great flexibility and adaptability to the specific area. 

You may come across the following typological solutions:

• LINEAR ELEMENT is suitable for the single user
• ISOLATED ELEMENT is suitable for 2-4 single users as the back-to-back arrangement allows for partial isolation. Not suitable for group conversations due to the difficult rotation movement and limited space
• CORNER ELEMENT is suitable for couples and group conversation

Once the type of seat has been chosen, we move on to the actual composition:

SEATS ALIGNED OR PARALLEL: as the distance between the seats varies, the possibility of conversation varies in an indirectly proportional way. 

CORNER SEATS: the distance between the two sections must be reduced in order to allow users to interact with each other.

SEATS IN GROUPS: if the distance between the sessions is varied, the offer in terms of interaction will also be varied.

BROKEN LINE SYSTEM: responds to a variety of needs.

CIRCULAR SYSTEM: suitable for single users.

CURVED SYSTEM: in the convex parts it responds to the needs of insulation while in the concave parts it guarantees easy communication.

It is possible to choose materials and finishes for all the products listed above. Today, more robust and resistant materials (galvanized steel) are preferred to traditional materials (wood, iron); the slightly higher initial cost is immediately compensated by simpler and less expensive maintenance. In fact, the greater resistance to atmospheric agents and vandalism typical of PVC-coated steel avoids the frequent repainting required in the event of damage.

From the point of view of installation, the seats must be anchored securely to the ground, which must be stabilized in the section below and in front of it. Sometimes it is necessary to have support surfaces next to the seats to allow for leisure, play and study activities. Especially in this case, maintenance must be assiduous and frequent to ensure satisfactory cleaning. To this end, special waste containers are inserted to raise awareness among citizens of respect for the environment. 

INFORMATION SIGNAGE
Inside the equipped green area it is sometimes possible to come across totems and signposts that provide useful information to visitors. They indicate directions, points of major interest, distances and parking. According to the law, since the signs are essential for the optimization of the use of the place by the user, they must have written text in Braille and audio buttons to facilitate the disabled.                                 
There are different models of signs on the market, differentiated according to the green area they are intended for: large urban park, small urban area, neighborhood garden. 
In any case, they will be painted in a matt dark green with writing printed on special anti-vandalism films to ensure better resistance.  

BIKE RACK
Increasingly in demand, bicycle storage spaces are made up of a tubular iron load-bearing structure and green galvanized steel racks. The standard dimensions of each station are 70 cm in length, 86 cm in height and 39 cm in width. 

Pyou bow

One of the main elements supporting the routes is characterized by parking lots that make walking and moving more comfortable. They are divided into bicycle parking lots and car parking lots and must be commensurate with the size of the garden and the expected flow.                       
Car parks are usually located at the access points to the internal routes. They are often temporary parking lots that see a frequent turnover of users who stop for short periods inside the green area. 
There are different types of parking areas for vehicles, commensurate with the type of spaces used for public greenery:

• surface parking
• underground or elevated parking lots

In order to optimize the use of the surface intended for parking, it is necessary to analyze the size of the cars and the maneuvering space they require, to appropriately design each individual parking space. The parking that allows you to make the best use of the space, especially when it is limited, is the comb type followed by the ribbon type which requires 25% more space. The types just mentioned are the result of the angle of inclination of the stall with respect to the direction of travel of the access lane:

• 0° parking spaces arranged parallel to the access lane (strip parking)
• 90° parking spaces arranged perpendicular to the access lane (comb parking)
• 30°/45°/60° parking spaces arranged in an inclined manner according to specific needs (sawtooth parking spaces)

As regards the choice of material for the paving of the parking spaces, since they are adjacent to a green area, particular attention must be paid. It is necessary to operate according to a sustainable and coherent perspective with respect to the context: it is essential to consider the chromatic and functional aspects.
Prefabricated concrete blocks, available on the market in various colors, self-locking blocks with multiple finishes and even gravel, grass and pebbles are optimal as natural solutions perfect for the context in question.                 
Parking spaces are spaced apart by strips of different materials and colors, so that the boundaries of each space are visible. It is also necessary to ensure that at least part of the available parking spaces are shaded by planting shrubs.  
In the case of the neighborhood garden, it is important that the parking lot is screened from the common green area, in order to create a visual and functional separation between pedestrians, users and cars. The solutions adopted are many: decorative elements, tree species, hedges, walls and shrubs that create a natural boundary aimed at the psycho-physical well-being of the user. 

PARKING FOR DISABLED PEOPLE

During the design process for the parking area for vehicles, the presence of parking spaces for disabled people must be planned. In common areas open to the public, according to the law, one parking space for disabled people is provided for every 50. This space must have a minimum length of 3,20 m, calculated on the size of a standard vehicle of 1,70 m to which is added a space of 1,50 m necessary for the movement of the wheelchair. The space must be easily connected to the sidewalk or to the path that leads to the green space and must be appropriately marked, with yellow stripes, a mark on the floor and a vertical sign. 

6. The garden and sustainability

The topic of sustainability today occupies an important space in the global debate; it finds application in various fields and also in that of urban planning. It is necessary to recreate the right balance between architectural artifacts and spaces used for public greenery; the optimal solution lies in parks and gardens that must be placed in the urban fabric with coherence. 

From an environmental point of view, it is important to take into account the available resources and, once the plant species, water resources and soil morphology have been identified, to exploit them to the maximum while respecting the existing context. 
It is good to encourage the choice of vegetation capable of capturing CO2 and performing important functions for biodiversity and acoustic well-being so as to reduce the use of artificial, expensive and impactful systems.
Furthermore, the neighborhood garden must be seen as a valid opportunity to reintroduce the typical species of the area, since the original biomes represent a fundamental landscape matrix.

The study of plant typologies is also necessary because it can perform important functions of passive cooling and heating with respect to the built fabric of the city. In fact, a careful green design that alternates horizontal and vertical surfaces, favoring the passage of air, is able to guarantee an excellent performance standard in environmental terms. This is extremely important for cities in which the heat island phenomenon records positive trends both during the day and at night due to the continuous absorption of solar radiation by the urban structure.

As for the social aspect, to obtain a good and successful project it is necessary to start from a careful analysis of the needs of the future users of the area. 
It is important to ensure comfort and well-being at a community level, in order to encourage the use of gardens and recreate the old sense of community and participation that has unfortunately faded in the hearts of citizens. 

It can therefore be concluded that parks, gardens and green areas in general are seen as urban lungs capable of improving environmental conditions within cities. However, too often poor quality and poor maintenance cause the loss of numerous shrubs, nullifying the actual functions of these spaces. Precisely for this reason, the need to adopt some good cultivation techniques aimed at creating natural habitats with a particular focus on environmental sustainability is emerging. 

The natural green project

According to the above, in order to be sustainable, project development should schematically follow the following phases:

• knowledge of the soil profiles and characteristics of the natural components
• acquisition and location of plant species
• organization of green volumes and proportions of the garden
• reconstruction of native habitats

The size of the available surface is the basic element that influences the design choices by defining the perception of spaces. The profiles of the land, if analyzed and exploited to the best, are decisive with respect to the aesthetic and qualitative success of the garden. A totally horizontal green area induces the observer to concentrate his attention only towards one point, often the central one.

In the case of small spaces, those interventions aimed at exploiting the space through solutions that amplify the visual field are optimal. In this sense, soft lines are preferable to geometric cuts and it is favorable to recreate hills that increase the depth of the space.

The next step consists in arranging the soil profile using integrated natural techniques. An increasingly used method is characterized by mulching. This is an alternative choice to paving that involves placing a micro-perforated plastic sheet over the entire walkable surface. The micro-holes guarantee permeability to rainwater and targeted irrigation. Usually a layer of aggregates (gravel, sand, bark) of variable thickness is placed over the sheet, which will allow for a more homogeneous and natural aesthetic.
Furthermore, mulching regulates the water balance of the soil because it reduces the evaporation of water present in the deeper layers which remains available to the roots of the trees. Along the paths, an integration consisting of a paved insert is usually inserted to make movement easier. 

Another key choice to restore the area's original natural balance concerns the plant field in terms of species and varieties to be used.
In addition to native plants, naturalized plants can be used, that is, those that have been planted in the specific area for a long time. 
In any case, the selection of vegetation elements is guided by functional, environmental and aesthetic reasons. Specifically, the type of shrub must be chosen with a view to the function it will perform: shading, visual barrier, ornamentation or even cooling. 
In the specific case of deciduous trees and plants, they will show their changing appearance during the succession of the various seasons, making climate changes more perceptible. 
On the other hand, evergreen species will keep their foliage throughout the year, maintaining a massive appearance, useful if you want to give visual weight to the entire garden. 
The most advantageous solution combines both typologies, which can be positioned alternately, offering glimpses and views that vary depending on the time of year.                                                                    
What is really important is the ability to foresee, from the early stages of the design process, the development of the chosen species in a given territory, proceeding in an aware and responsible manner. In fact, especially in urban areas, it is essential to maintain the functions and aesthetic result over time, avoiding damage to things and people. If the spaces are limited, as often happens in neighborhood gardens, it is preferable to opt for plants with little root development, since as they grow, the roots would constitute an obstacle for cycle and pedestrian paths. Furthermore, it is mandatory to avoid plants that can cause allergies, that have poisonous flowers and fruits or thorns and spines, as they are dangerous elements for citizens. In urban areas, species with a greater capacity to absorb CO2 and release oxygen are indicated, in order to combat excessive pollution. In addition to shrubs, hedges are multifunctional elements with a high aesthetic value; they must be sized according to needs and must not present incongruence and discontinuity in their development.

After choosing the type of plants and shrubs that best fit the lot where the garden will be built, it is necessary to organize the compositional scheme in order to obtain a harmonious and coherent result with the surrounding environment. Although often difficult to perceive, there is a real hierarchy, which if respected, will give satisfactory results. In fact, the harmonious succession of vegetation levels of different heights allows you to visually move from the herbaceous level to the shrubby one and finally to the arboreal one in a gradual and balanced way. Usually, there is a tendency to focus attention on an element that will act as a point of reference with respect to all the other components. This will create a harmonious progression that will allow you to perceive the spaces as being naturally related to each other. After establishing the design unit, the proportions are defined accordingly. If the ground presents movements, by correctly placing the plant masses, pleasant visual effects will be obtained.

What is fundamental is that there is a proportion between volumetric masses and expanded forms; the former are constituted by all the natural and anthropic encumbrances while the latter are characterized by paths, bodies of water and meadows. The vegetal element and the constructed one (which must be reduced as much as possible, in relation to the specific needs) must merge in order to recreate natural microenvironments similar to native habitats, blending perfectly with the context. 
Finally, in the face of a conscious and careful planning, it is important to keep in mind how the maintenance of the space will play a fundamental role in the success of the green area.

Water element management

As shown by sector studies, areas containing different percentages of greenery manage rainwater runoff differently. It is easy to deduce that a higher quantity of plant elements corresponds to a greater absorption of water by the soil.  
In fact, with the increase of impermeable surfaces (recreated by the hand of the designer), the quantity of rainwater that infiltrates into the subsoil decreases.

GREEN AREA 100% water: 10% flows, 40% evaporates, 50% is absorbed

GREEN AREA 50-65% water: 30% flows, 35% evaporates, 35% is absorbed

GREEN AREA 0-25% water: 55% flows, 30% evaporates, 15% is absorbed

For this reason, in the case of the neighborhood garden, if the pavements that characterize paths, accesses and functional areas occupy a large portion of the available surface, it is necessary to introduce systems that better manage rainwater runoff. An example of this is the stormwater box, filtration systems that collect and treat rainwater that cannot be collected by the ground.
These are tanks made of different materials (bricks, stones, concrete) filled with soil and plants (stormwater planter box) or gravel and pebbles (stormwater filter box) that can be placed in any open space lacking permeable surfaces. 

Graphical diagram of a stormwater planter box. Source: https://www.ci.sandy.or.us/Planter-Boxes/ 

If you do not want to intervene with this type of solution, it is essential to increase the green walking surface. Lawn expanses are perfect in case of large spaces, while if the area is small, grassy self-locking panels can be inserted in the parking areas or in correspondence with paths and trails. 

The use of ecological materials

Today there is an ever-increasing need to seek innovative solutions that are in balance with the environment and that ensure satisfactory energy and economic savings.                            
Green urban design deals with dressing the city and its spaces with a particular sensitivity to environmental sustainability, prefers eco-friendly materials, encourages the recycling of resources and sets itself the objectives of quality, durability and economic convenience. 
By sustainable materials, we mean all those substances that are non-toxic, recyclable and produced through processes that use alternative energy. The mistake that has been made in the past and in part, unfortunately, still today, consists in considering the material by evaluating only the intrinsic cost and not the environmental cost related to extraction, production, transport and future use. In fact, the processing phases of a product cause the consumption of huge quantities of resources every year and produce a high level of pollution. 

The winning approach is instead to consider the entire life cycle of materials, hypothesizing a second life made possible through reuse. 

The materials will therefore be perfect:

• Recyclable
• Locals that come from the area in which we are working
• Free from pollutants and harmful components
• Coming from renewable resources with low exhaustibility and available in abundance

Sometimes materials from demolitions or on-site interventions are used; these are choices that guarantee significant economic savings but also favor the preservation of the identity of the place. In this way, thanks to new technologies, ancient materials can be reused and thus find new utility. 

Of course, these good design practices must always take into account the performance capabilities of the material that must ensure practicality, resistance and aesthetics to the furnishing components. Furthermore, the reduction of waste of excess material and the streamlining of production and transport processes ensure a significant reduction in costs. 

An example of intelligent recycling of materials used in urban gardens is represented by the anti-trauma flooring that is inserted in play areas near slides and swings. Made with recycled rubber, they are resistant, non-slip and safe, as well as requiring low maintenance. In this specific case, often, even the play structures are produced using recycled plastics that resist atmospheric agents well and in the event of vandalism require simple washing. Furthermore, the treatments to which the recycled materials are subjected make the finished product suitable for users (children) because it is safe and non-toxic.

Recycled plastics are perhaps the most used among the recovered materials: starting from high quality waste that would otherwise be disposed of, we obtain regenerated and ready-to-use materials. Seats, tables, baskets, fences, have excellent performances of resistance to bad weather, oils, salt, UV rays, in addition to being ecological and having a low environmental impact. 

It is therefore of fundamental importance that the designer is aware of the possibility of using and reusing industrial waste, local materials that are no longer in use or in the process of being disposed of.                         
As we have seen, in fact, it is a responsible choice because in addition to implying a reduction in construction costs, the environment and the context in which one operates are respected without sacrificing functionality and aesthetics. 

7. The smart garden

Today the concept of smart seems to recur too often and sometimes even inappropriately.  
In fact, there is a great distance between the abuse of the term in simple theoretical discourses and its real use. It is necessary to understand the deeper meaning of the term and work to ensure its real application. By “smart city” we mean an intelligent city that combines innovation, optimization of resources and energy saving and ensures citizens efficient and accessible services. 

In the specific case of green spaces, they will be considered an integral part of the smart city and will have to be usable and cutting-edge. Today the field of design and urban furniture is very active in the study of increasingly smart solutions, in terms of sharing and energy saving. Below are some examples of conscious and responsible intervention within neighborhood parks and gardens.  

Contemporary furniture between design and energy saving

Research in the field of outdoor design today is aimed at providing integrated solutions that combine traditional functionality and new technology. These are design choices that arise from the needs of a changing and increasingly computerized user base. 

The public garden is considered a vital space, a place of meeting and exchange, perfect for welcoming accessible and eco-friendly design solutions. If innovation aimed at reducing waste is the master, then we can talk about projects on a human scale. In the urban context, increasingly innovative solutions are chosen regarding the finishes and lighting systems of gardens and in some cases the furniture. 
For example, as regards pavements, the use of photocatalytic materials is spreading, capable of separating fine dust thanks to titanium dioxide which captures and reduces polluting substances, subsequently washed away by rain.
Another solution chosen for the walking surfaces is characterized by photovoltaic tiles. These are luminous glass blocks powered by solar energy stored during the day; each brick lights up at sunset thanks to the LEDs inserted inside. In this way the space can also be used in the evening hours without excessive waste.

Precisely on the subject of lighting, there are various intelligent solutions that are used in public spaces. Increasingly equipped with sensors that are activated by the passage of users, the devices are designed to contain electricity consumption and pollution. In fact, according to recent studies (International Energy Agency), urban lighting is responsible for 6% of CO2 emissions into the atmosphere and 19% of global energy consumption. The field of intelligent street lighting is gaining great consensus today because solutions aimed at improving the current situation are urgently needed. This is why in green public spaces, street lamps are perfectly positioned that turn on and adjust the intensity and direction of the light beam according to the flow of people and turn off when there is no passage. 

Another important aspect to consider within the smart public garden is characterized by the services and all those elements that contribute to improving its efficiency. 
Outdoor furniture deals with the study and design of furnishing accessories intended for open spaces. There are numerous experiments and proposals that intend to enrich traditional solutions by inserting innovative aspects.

An example of this is the SMART BENCH, seats designed to improve relaxation breaks with the addition of shared services such as local microclimate control, the ability to recharge your smartphone and even provide information on where you are via Wi-Fi hotspots.
The electronic devices are protected from external agents and the refined design makes the seat aesthetically pleasing as well as functional. The materials used are eco-sustainable and resist wear and tear and atmospheric agents well. Often, this type of bench is equipped with photovoltaic modules that make it completely independent for the production of energy necessary to recharge the battery of portable devices. 

Inside public green areas, depending on the space available, it is also possible to find sports equipment that can perform multiple functions. Real open-air gyms where, through physical effort, users produce energy that can be reused at a later time. All the equipment is weatherproof and is equipped with a USB port that allows the use of smartphones and electronic devices.

Sometimes there are also information totems that indicate the amount of energy produced, the kcal burned and the distances traveled. In some cases these screens are interactive and through a touch panel it is possible to exchange information and navigate the web. These elements are waterproof, have an anti-breakage structure and are equipped with an audio system and a Braille panel to allow their use also by the disabled. 

Since every neighborhood garden has an area designated for parking for users, there are also very useful smart solutions in this sense that can facilitate users by saving them precious time.
A parking management system has been introduced that, thanks to a free APP that can be downloaded by everyone, allows you to check in real time the availability of parking spaces near the green area. Monitoring works thanks to the insertion of sensors on the ground in correspondence with each individual parking lot. 

When even security becomes smart

The public garden project must necessarily include measures that guarantee safety within the spaces, because it is well known that if the citizen feels safe he is encouraged to frequent a place, otherwise he is not. For this reason, also in this field, innovation improves the performance of the elements arranged for the protection of users. The SOS columns are an example of this, connected to the control center and the emergency number, they allow rapid audio and video communication and prompt intervention in case of need. For the correct functioning and consequently the rapid use, however, the meticulous and careful maintenance of the devices is of fundamental importance.
Another important safety measure is given by the video surveillance system of the area; the cameras are connected to the competent bodies ready to intervene in case of danger. 
In this way, the above solutions allow citizens to be an integral part of the control of the urban territory, thus contributing to their own safety and that of other users.

Safety devices inside a green area. Source: http://www.sicurezzaetica.com

Participatory design

If the project interpreted in a smart way also includes the participation of future users, it will have an added value of fundamental importance. For example, involving children through recreational workshops for the planning of play spaces will help to achieve a more satisfactory result. Likewise, users of different age groups and social backgrounds will be able to contribute to the success of the project by expressing their particular needs and proposing valid solutions aimed at satisfying them.
Finally, this type of approach is useful to recover the sense of community and belonging to the place where one lives, as well as promoting sociality between individuals.

8. Examples of neighborhood gardens

Architects and designers often find themselves having to deal with the complicated burden of redevelopment and reconversion of urban voids or abandoned areas. The effort is to restore identity to places that have become anonymous residual spaces, reconverting them into areas intended for the community. Furthermore, since today the urban environment is poor in green areas, the public environment is interpreted in a green key and made a mix of technological innovation, sharing and sustainability. 
Below are some examples of successful design involving contemporary neighborhood gardens, intended for specific functions or born from very specific intentions. 

Piazza Risorgimento – Turin, 2016 – The smart garden

It was the first smart square in the city, able to combine technology and sustainable innovation. Born from the urban redevelopment project of the Campidoglio district, the square was a real social experiment; in a temporary form (3 months) it received great consensus among citizens. The promoter of the project was Planet Idea, a consultancy body aimed at spreading integrated innovation in the urban area.  
The main guidelines of the project were the sustainability of the solutions adopted, the advanced technology of the systems and the sharing of the services offered. Among the solutions proposed were an open-air gym capable of producing useful energy through the physical exercise of the users, a relaxation area complete with musical seats and an area used for urban gardens. Furthermore, some specific choices, aimed at energy saving, contributed to raising awareness among users regarding these issues. Examples of this are the photovoltaic tiles inserted into the floor and the information totems powered by solar energy.
A contribution has also been made from a social point of view: through the planting of common vegetable gardens and bookcrossing, an initiative aimed at sharing readings and books made available to the community. 
It has been demonstrated how this type of urban intervention, attentive to the needs of citizens and in step with the times, has provided an excellent result from an economic, environmental and social point of view.  

Source: https://www.planetsmartcity.com 

Viale Montello – Milan, 2013 – The sustainable garden

The lot where the “Lea Garofalo” Community Garden now stands has remained abandoned for years, waiting to be used as an anonymous parking area. 
It was thanks to the contribution of the neighborhood's residents, architects, nursery gardeners, designers, the Giardini in transito Association and the Municipality of Milan that the area's fortunes changed. From the beginning, the intent was to give new life to the space by returning it to the urban fabric but in a green way. 
The project's core was the desire to recover pre-existing biodiversity through the introduction of native plant species, plants and new urban gardens. This decision was also dictated by the desire to recreate a community environment that had become extinct in the area. 
The choice of low-cost materials characterized the management of the space and the construction of the walkway, flower beds and seats, due to a limited budget. The management model today provides for the active participation of citizens, protagonists from the early stages of the redevelopment process, who make the place alive and lived every day. 
Within this neighborhood garden, numerous social initiatives take place that link it to events throughout the city. The promotion of exhibitions, cultural events and recreational events represents an important opportunity to make an area that until recently had been forgotten, an excellent hub that attracts flows of people from the rest of the city. In this way, urban planning fulfills the important task of creating social networks and connections between distant areas that belong to the same urban context. 

Freilassing, Bavaria – Germany – The Garden Dedicated to Fitness

It is a peri-urban garden the size of a football field, dedicated entirely to physical activity. Intended for a varied range of users, it is conceived as a meeting and exchange place accessible 24 hours a day, 7 days a week. 

The green area dedicated to outdoor sports is divided into four sections, each of which offers services to users of different ages. The first portion is intended for more trained athletes and is made up of specific equipment suitable for the most demanding exercise. Two areas follow that offer cross training activities, training suitable for everyone, including the elderly and disabled. The last area has been left free of specific structures in order to increase yoga and outdoor dance courses. The outdoor gym aims to attract people from all over the town and to involve local sports associations. 
The garden with a sporting vocation has several objectives: 

• encourage citizens to do physical activity to counteract sedentary lifestyles
• promote multigenerational use of the same spaces, combating the exclusion of the weakest and most disadvantaged sections of the population
• increase the sense of community

Furthermore, the high quality of sports equipment made with resistant, safe and long-lasting materials is guaranteed.