DESCRIPTION OF THE INVENTION

FIELD OF THE INVENTION

The invention relates to methods and systems for watering green walls, also known as vertical gardens, living-wall systems, or by the acronym LWS. Green walls represent a way of arranging ornamental plants parallel to walls of pre-existing architectural structures, realising a sort of vertical garden. In this way, the aesthetic appeal of the architectural structures is improved and thermal and acoustic insulation is increased. Further, green walls contribute to reducing fine particles, or "PM10" particles.

DESCRIPTION OF THE PRIOR A T

To obtain a green wall it is necessary to realise a relative support that can be constituted by one or more special panels for green walls, fixed to one another, the extension of which is substantially planar. Each panel comprises a relative frame, a relative containing structure, permeable to water, fixed to the frame and defining a plurality of housings. A rooting substrate is then inserted in the housings, which enables the roots of the plants to settle in. Subsequently, the plants are in these housings containing the rooting substrate, or other plants are transplanted therein. As the plants need to be watered, watering devices are provided, fixed to the green wall, which are connectable to a source of watering liquid, which can also be constituted by the municipal supply or a water tank. These watering devices, also known as driplines, are predisposed for uniformly distributing the watering liquid (for example water or a solution of water and a nutrient, and/or a fertilizer, and/or an anti-parasite treatment) along a watering line, typically horizontal. Each watering device comprises relative regulating means (for example a solenoid valve or an immersion pump in where tanks are used) for regulating an inflow of a liquid to the watering device and a consequent draining thereof from the watering device. These watering devices typically comprise a hydraulic tube in which a plurality of holes is fashioned, aligned along the watering line with the aim of uniformly watering the wall along the line. The liquid outflowing from a watering device, by effect of gravity and the fact that the containing structure is permeable, tends to move downwards, and is progressively absorbed by the containing structure, the rooting substrate and the roots of the plants.

Unless it is particularly low, a green wall usually includes the presence of a plurality of relative panels and a plurality of watering devices, arranged at various heights so as to be able to water different portions of the green wall. In general, watering devices are controlled by an electronic control unit, for example an electronic control unit predisposed for following a determined watering programme by periodically commanding, for a determined time period, the opening of all the regulating means installed in the green wall. Note that if the quantity of watering liquid distributed is lower than what is necessary for the green wall, there will be zones of the green wall where there is excessive dryness. On the contrary, in a case of overdosing, the watering liquid will tend to gather towards the bottom of the green wall and can even percolate from the green wall, causing wastage and a containing problem of the liquid itself. Further, the plants arranged in the low part of the wall will suffer from over- watering.

Even though the electronic control unit can be programmed to dispense water following a predetermined watering programme (for example with different watering times over the range of the day), the real climatic conditions and the consequent status of irrigation of the rooting substrate are not taken into consideration for the purposes of the definition of the watering times. Therefore it can occur that the watering devices dispense the watering liquid even through wall is already excessively moist due to poor evaporation, for due to the presence of rain, or it might not be watered if the rooting substrate is dry, at least in some areas. In both cases, the plants are subject to repeated stress, from flooding and/or dryness, which can lead to a worsening of the plants' health conditions, the aesthetic appeal of a part of the green wall, and consequently there might be reductive effects on the environmental benefits such as a deterioration of the heat and acoustic insulation of the green wall. This might even lead to the death of the plant and/or the need to call upon specialised operators in the matter of green walls to repair the ensuing damage. In fact, the main cause of mortality of the plants in green walls is the impossibility of ensuring correct hydration and the known watering methods and systems of a green wall do not enable maintaining of a hydration condition of the rooting substrate that is stable over time, nor do they guarantee a sufficient hydration condition.

Humidity sensors are known that exploit the conductivity of a rooting substrate to enable a timely measuring of the relative humidity at a predetermined measuring point. The sensors detect a value expressed in millivolts which can be correlated to the humidity in the rooting substrate. The humidity sensors are connectable to the control units and can also be used to carry out calibration curves of any rooting substrate. The curves can be obtained by adding measured quantities of water to a determined quantity of rooting substrate arranged in a container with openings on the bottom, while measuring the value of potential difference at each addition. When the water flows out of the bottom, there is a humidity value of 100% in the rooting substrate to which the quantities of water added during the measuring process can be related. The collated data can be represented in a graph, such as for example the graph shown in figure 1 , which constitutes a calibration curve for the given rooting substrate. As can be noted from figure 1 , the ordinates report the volumetric content of water in the substrate, in this case expressed in millilitres, but can be expressed also in gram or as a percentage (for example cubic metres of water in cubic metres of total volume). By way of example a scientific article is cited which illustrated how to obtain the calibration curves, namely Giovanni Bitella et al. "A Novel Low-Cost Open-Hardware Platform for Monitoring Soil Water Content and Multiple Soil-Air-Vegetation Parameters" Sensors 2014, 14( 10), 19639- 19659; doi : 10.3390/s 141019639.

SUMMARY OF THE INVENTION The main aim of the present invention is to obviate the drawbacks in the prior art, in particular enabling a suitable watering of the green' walls, with the aim of guaranteeing a condition of sufficient dryness of the rooting substrate of the green wall over time in order to reduce flooding or stresses on the relative plants.

A further aim of the invention is to limit, with regard to the dimensions of the green wall, the number of watering devices required for obtaining the suitable watering. An objective of the invention is to enable suitable watering of the green wall by limiting the consumption of watering liquid and the relative percolation thereof from the bottom of the green wall, thus limiting waste.

The invention further provides an automatic watering system for green walls which is constructionally simple and economical as well as reliable in use.

The above aims and objectives are attained with a method and a system for automatic watering of a green wall according to the independent claims.

As will be illustrated in the following, the automatic watering method of a green wall according to the invention and the automatic watering method for actuating it enable suitable watering which: guarantees that the plants in the wall are less subject to incidents of flooding or dryness with respect to the prior art; enables minimising consumption of watering liquid, and therefore waste thereof, and the number of watering devices required for obtaining the suitable watering. In particular, by using the method a condition of suitable hydration in the rooting substrate is achieved, and is stable over time.

In fact, by actuating the method using the watering system, the watering device of each reference system will dispense the watering liquid only when the absolute value of the relative calculated numerical value is lower than the first reference parameter, which is correlated to a condition of sufficient hydration of the green wall necessary for maintaining the plants of the green wall in good health. Note that the calculated numerical value for each reference system is proportional to an average humidity value of the green wall relative to the zone in which the relative measuring points are arranged.

Each green wall is characterised by a relative containing structure, a relative rooting substrate and relative plants which, given an equal quantity of watering liquid dispensed, can have a different effect on the humidity present in the green wall. Therefore, the value of the first reference parameter can vary from green wall to green wall and it is the operator's task to establish it, time-by-time, on the basis of his or her experience or on the basis of the calibration curves. For example, the operator might decide that the first reference parameter corresponds to a measured potential difference in the rooting substrate or in the compressed rooting substrate-plant present in the green wall in the humidity conditions adjudged to be the minimum indispensable amount. In this case, the value of the first factor of multiplication and the multiplication term will be "1". Should it instead be desired to express the first reference parameter in terms of percentage humidity, a calibration curve can be used that relates to the rooting substrate or the compressed rooting substrate-plant.

' The applicant has found that the arrangement of the measuring points in accordance with the claimed method enables using an automatic watering system in which the number of the relative sensors and the devices is as small as possible, which enables obtaining the suitable amount of watering, and which is characterised by an efficiency of greater than 50%. By efficiency is meant the percentage ratio of the number of cases in which stresses are not found (both dryness and flooding stress) and the number of cases in which stresses become evident. The reading of the humidity in a plurality of points and with a multiplicity of humidity sensors, external of the watering system, enables calculation of this efficiency. Further, with the invention, the consumption and waste of watering liquid is significantly reduced with respect to the prior art.

The watering liquid can comprise, or be constituted by, water and a watery solution comprising nutrients for plants, bio-stimulants and an anti-parasite treatment. These additions to the water can enable application of products necessary for maintaining the plants in optimal physiological conditions, without its being necessary to apply a localised manual treatment to the wall, at the same time reducing the maintenance costs.

BRIEF DESCRIPTION OF THE DRAWINGS:

Specific embodiments of the invention will be described in the following part of the present description, according to what is set down in the claims and with the aid of the accompanying tables of drawings, in which:

- figure 1 is a calibration curve of a root substrate obtained by known methods;

- figure 2 is a front schematic view of a green wall to which an automatic watering system according to the invention is associated;

- figures 2a and 2b are schematic views, respectively lateral and from above, of a green wall and of the automatic watering system of figure 2;

- figure 3 is a diagram indicating the percentage of humidity as a function of time of a green wall according to the automatic watering system to which it is associated;

- figure 4 is a diagram illustrating the definition of the reference systems and the measuring points according to the method of the invention;

- figure 4A is a diagram illustrating the definition of the reference systems and the measuring points according to the method of the invention;

- figure 5 is a diagram illustrating the definition of the measuring points of a reference system according to the method of the invention;

- figure 6 is a diagram showing the definition of the position of the watering line according to the method of the invention;

- figures 6A - 6G schematically illustrate the humidity of a portion of green wall as a function of the positioning of the watering line of figure 6 and figure 6H illustrates the scale used in figures 6A-6G;

- figure 7 is a graph showing the number of cases of dryness stress, excess humidity stress and total stress as a function of the positioning of the watering line;

- figures 8A, 8B, 8C show graphs illustrating the efficiency of the automatic watering method as a function of the percentage variation of the relative coefficients, respectively: the second and third measuring points; the first measuring point, and the fourth and fifth measuring points of a reference system according to the method;

- figure 9 is a schematic view illustrating various inclinations of the green wall with respect to a horizontal plane;

- figures 10A - 10L graphically illustrate the humidity at points of a green wall at various inclinations thereof and figure 10M is the scale used in figures 10A - 10L; and

- figure 1 1 is the flow chart of the steps carried out by the automatic watering system of the invention in actuating the automatic watering method of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

With the purpose of more clearty highlighting the characteristics of the invention, the figures relating to a green wall (denoted by reference numeral 10) do not provide detailed illustration of the relative support of the relative panel/s, nor the relative containing structure, nor the relative housings, nor the relative rooting substrate, nor the relative plants.

With reference to figures 1 - 10, the automatic watering method of a green wall according to the invention comprises steps of:

A) predisposing a green wall having a substantially planar support inclined by at least 25° with respect to a horizontal plane;

B) defining at least a first number (Nsr) of reference systems, each of which: is two-dimensional Cartesian: an abscissa X and an ordinate Y; is substantially coplanar to the support, has a relative origin of coordinates: X = 0; Y = 0 and delimits four relative quadrants; the origin of each of the reference systems arranged in a different cell (101 ) of a two-dimensional grid (100) (see figure 4A), which is substantially coplanar to the support, and has a number of relative cells (101) equal to the first number (Nsr) of reference systems and a number (Nr) of horizontal lines of cells (101) and/or a number (Nc) of vertical columns of cells (101), wherein:

Nsr =Nr x Nc

where Nsr is equal to the first number (Nsr) of reference systems, Nr is equal to the number (Nr) of horizontal lines of cells (101), and Nc is equal to the number (Nc) of vertical columns of cells ( 101);

C) defining a second number (Ns) of measuring points (a, b, c, d, e, f, g, h, 1) given by:

Ns = 5 + (Nr-1) x 3 + (Nc -1) x 3 + (Nr-1 ) x (Nc- 1) x 2

Nr is equal to the number (Nr) of horizontal lines of cells ( 101); and Nc is equal to the number Nc of vertical columns of cells (101);

D) associating to each reference system:

- a relative first measuring point (e) at the origin of the relative reference system;

- a relative second measuring point (a) at an upper left quadrant of the relative reference system within the following intervals of coordinates X = from -90 to - 13 cm; Y = from 41 to 87 cm;

- a relative third measuring point (b) at an upper right quadrant of the relative reference system within the following intervals of coordinates X = from 13 to 90 cm; Y = from 41 to 87 cm;

- a relative fourth measuring point (c) at a lower left quadrant of the relative reference system within the following intervals of coordinates X = from -81 to -16 cm; Y = from -97 to -42 cm;

- a relative fifth measuring point (d) at a lower right quadrant of the relative reference system within the following intervals of coordinates X = from 16 to 81 cm; Y = from -97 to -42 cm;

wherein when a plurality of reference systems are comprised, each first reference system has two measuring points, arranged on relative adjacent quadrants, in common with a second reference system adjacent to the first reference system;

E) defining, for each included reference system, a watering line (80) arranged above, by a maximum distance (Di) of lower than 25 cm, the second and the third measuring point (a, b) of the relative reference system or passing through the second and third measuring points (a, b) of the relative reference system;

F) measuring, for each included reference system, a first, a second, a third, a fourth and a fifth electrical potential value (V I , V2, V3, V4, and V5), respectively at the relative first, second, third, fourth and fifth measuring point (e, a, b, c, d);

G) calculating, for each included reference system, a numerical value (M) proportional to a sixth electrical potential (Vm), given by:

M = o (Kl x VI + K2 x V2 + K3 x V3 + 4 x V4 + K5 x V5) / 5

wherein:

K0 is a numerical term that is different to zero;

VI , V2, V3, V4, and V5 are respectively the relative first, second, third, fourth and fifth values of measured electrical potential (V I , V2, V3, V4, V5);

Kl is a first numerical coefficient, relative to the first measuring point, comprised between 0.44 and 1.54;

K2 is a second numerical coefficient, relative to the second measuring point, comprised between 1.2 and 2.88;

K3 is a third numerical coefficient, relative to the third measuring point, comprised between 1.2 and 2.88;

K4 is a fourth numerical coefficient, relative to the fourth measuring point, comprised between 0.27 and 0.70;

K5 is a fifth numerical coefficient, relative to the fifth measuring point, comprised between 0.27 and 0.70;

Fl is first a predetermined numerical factor of multiplication that is different to zero; and

the value of the sixth electrical potential (Vm) being given by:

Vm = (Kl x VI + K2 x V2 + K3 x V3 + K4 x V4 + K5 x V5) / 5

wherein

Vm represents the sixth electrical potential (Vm) and V I , V2, V3, V4, V5, Kl , K2, K3, K4, and K5 are defined as above.

H) comparing, for each included reference system, the absolute value of each numerical value (M) calculated with the absolute value of a first reference humidity parameter (PI ) which is: relative to a condition of sufficient hydration of the green wall and proportional to a predefined first reference electrical potential (Vs); and given by:

PI = Fl x Vs

where:

PI represents the first reference humidity parameter (P I);

Fl is a first predetermined numerical factor of multiplication that is different to zero; and

Vs is the first reference electrical potential (Vs);

for:

- when the absolute value of the numerical value (M) is lower than the absolute value of the first reference humidity parameter (PI), uniformly distributing a watering liquid along the watering line (80) of the relative reference system for a predetermined first time interval (Tl), and leaving a second predetermined time interval (T2) to pass;

I) reiterating steps F) - H).

The second time interval T2 is preferably greater than the first time interval Tl .

The definition of the reference systems and the measuring points can be observed in figures 2 and 4-5. Figure 2 schematically illustrates a green wall (10) to which a single reference system is associated, the measuring points of which are denoted as e, a, b, c, d. Figure 4 schematically illustrates a green wall (10) to which four reference systems are associated, the measuring points of which are denoted as SRI, SR2, SR3, SR4. The first thereof, high up on the right, denoted by reference (SRI), includes five measuring points (e, a, b, c, d), of which the relative fourth and fifth measuring point (c, d), arranged in the relative lower quadrants, are in common with a second and adjacent reference system (SR2) where they constitute the second and third measuring points (c, d) thereof, arranged in the relative upper quadrants. The third and the fifth measuring point (b, d) of the first reference system, arranged in the right quadrants thereof, are in common with a third and adjacent reference system (SR3), where they constitute the second and fourth measuring point (b, d) thereof, arranged in the relative left quadrants. The watering lines are denoted by reference numeral (80) and the distance thereof from the second and third reference point of the relative reference system is denoted by reference (Di).

In the following the calculations of the number of measuring points relative to figures 4 and 4A are shown by way of example: grid with 2 lines and 2 columns: Ns = 5+1 x3+1x3+1x1 x2 = 13; grid with 4 lines and 3 columns: Ns = 5+(3- l)x3+(3- l )x3+(3-l)x(3-l)x 2= 25;

The number of measuring points (Ns) of a row of reference systems flanked horizontally or vertically is calculable by considering that row of systems as being arranged in a grid which includes, respectively, 1 column and n lines that is equal to the number of vertically flanked reference systems and/or 1 line and n columns equal to the number of reference systems flanked horizontally.

In the first case: Ns = 5 + (Nr-1) x 3 + (Nc - 1) x 3 + (Nr- 1) x (Nc-1 ) x 2 = 5 + (Nsr-1) x 3 +0 +0 = 5 + (Nsr-1) x 3 Likewise in the second case Ns = 5 + (Nr- 1) x 3 + (Nc - 1) x 3 + (Nr-1) x (Nc- 1) x 2 = 5 + +0 + (Nsr-1) x 3 + 0 = 5 + (Nsr-1) x 3 where Ns is the number of measuring points Ns and Nsr is equal to the first number (Nsr) of reference systems in the row.

With reference to figure 5, this figure relates to a single reference system and shows the positions in which it is possible to define the measuring points (a, b, c, d) and in the green wall (10) as in figure 2. The watering line (80) preferably has an inclination, with respect to the relative axis of the abscissa X, of lower than 10°, more preferably lower than 5° and advantageously is arranged parallel to the coordinates of the X.

The watering method of the invention can be demonstrated to be able to maintain an almost-constant degree of humidity. Further this enables limiting the consumption of watering liquid and the relative percolation thereof from the bottom of the green wall (10). In this matter reference is made to figure 3 which is a diagram indicating the percentage of humidity as a function of time of a green wall (10) according to the automatic watering system to which it is associated. In this diagram the continuous line relates to the method of the invention: the broken line with the shorter dashes relates to a first watering method of known type in which the green wall ( 10) is watered and 6 am. and 6 pm. for 15 minutes, and the broken line with the larger dashes relates to a second watering method of known type in which the green wall (10) is watered from 6 am. to 8 pm. every hour for one minute. Note that the first watering method of known type produces a quantity of excess of the watering liquid of 1.52 litres per day, while the second watering method of known type has an excess of 1.32 litres and the method of the invention has only 0.82 excess per day. Further the consumption watering liquid of the method of the invention is reduced by 44.5% and 36.1% in comparison, respectively, to the first and second watering method.

The applicant has verified an efficiency of 95% for the method by using the method for watering a vertical green wall (10) using the following first, second, third, fourth and fifth numerical coefficients (Kl, 2, K3, 4, 5) and a single reference system with the relative following measuring points in a relative first position indicated in the following:

- Kl = 1 ;

- K2 = 2;

- K3 = 2;

- K4 = 0.5;

- K5 = 0.5;

- the first measuring point (e): X = 0; Y = 0;

- the second measuring point (a): X = -25 cm; Y = -55 cm;

- the third measuring point (b) X = 25 cm; Y = 55 cm;

- the fourth measuring point (c) X = 25 cm; Y =—55 cm;

- the fifth measuring point (d) X = 25 cm; Y = 55 cm.

To determine the intervals of coordinates of the measuring points of a second, third, fourth and fifth position, in which the variation in efficiency of the method according to the invention is respectively 90%, 80%), 70% and 50%, the following were used: a single reference system (Nsr) and the first, second, third, fourth and fifth numerical coefficients (Kl , K2, K3, K4, K5); the same reference parameter (P I ) of humidity and the same multiplicative factors (F l) and the same time intervals (Tl, T2), previously used in accordance with the watering method according to the invention which has provided a 95% efficiency. The table (1) summarises the results pertaining to the determining of the measuring points as a function of the efficiency attained by the relative watering method according to the invention and reports, for each measuring point (a, b, c, d, e) and, with regard to the reference system, the coordinates or intervals of coordinates of the relative first, second, third, fourth and fifth position.

Table 1

In figure 5 the first position of the five measuring points is denoted in its entirety by the symbol "+", while the first position of the first, second third, fourth and fifth measuring points e, a, b, c, d, is denoted, respectively, by references el, al, bl, cl, dl. The edges of each square surrounding a relative first position al, bl, cl, dl of the second, third, fourth and fifth measuring point a, b, c, d have, given other conditions being the same (F, K0, Kl, 2, K3, K4, 5, PI etc..) the same efficiency with a margin of error of 5%. With reference to figure 5, each measuring point e a, b, c, d, relates to a relative second, third, fourth and fifth position along, respectively, the perimeter of the first, second, third and fourth square surrounding the relative position el, al, bl, cl, dl, starting from the relative first position el, al, bl, cl, dl. The points indicated by a filled circle indicate the coordinates which distance in an external direction from the first position. The points indicated by a non-filled circle indicate the coordinates which distance in an internal direction from the first position.

With reference to figure 5, the positioning of the second, third, fourth and fifth measuring point within the above-mentioned intervals of coordinates, as defined in claim 1, must be done within or on the borders of the fourth and most external square which surrounds the relative position al , bl , c l , dl .

As can be observed in table 1 , by increasing the value of the coordinate, for example from a2 towards a5, the distance of each position with respect to the first position increases and the precision of the automatic watering method decreases. It follows that a method is preferred, according to the invention, in which the definition of the second, third, fourth and fifth measuring point takes place respectively within the fourth, third, second position or in the first position, since they lead to a progressively increasing efficiency. Therefore it is progressively preferable that:

- the second measuring point (a) is situated within the following intervals of coordinates: X = from -67 to - 15 cm; Y = from 44 to 81 , Y = from -44 to -19; Y = from 48 to 74, x = from -37 to -22; and Y = from 51 to 68, and in the following coordinates X = -25 cm; Y = -55 cm;

- the third measuring point (b) is situated within the following intervals of coordinates: X = from 15 to 67 cm; Y = from 44 to 81 cm; X = from 19 to 44; Y = from 74 to -44, X = from 22 to 37; Y = from 51 to 68, and in the following coordinates X = 25 cm; Y = 55 cm;

- the fourth measuring point (c) is situated within the following intervals of coordinates: X = from -57 to - 19 cm; Y = from -92 to -45 cm; X = from -49 to -21 ; Y = from -86 to -48, X = from -37 to -23; Y = from -71 to -51, and in the following coordinates X = 25 cm; Y = -55 cm:

- the fifth measuring point (d) is situated within the following intervals of coordinates: X = from 19 to 57 cm; Y = to cm; -92 to -45 cm; X = from 21 to 49; Y = from -86 to -48, X = from 23 to 37; Y = from -71 to -51 , and in the following coordinates X = 25 cm; Y = 55 cm.

To determine the intervals of the numerical coefficients (Kl , K2, K3; K4, K5) of the five measuring points of a reference system in which the variation in efficiency of the method according to the invention is respectively 90%, 70% and 50%, the following were used: a single reference system (Nsr) and the first, second, third, fourth and fifth numerical coefficients (Kl , K2, K3, K4, K5); the same reference parameter (PI) of humidity and the same multiplicative factors (Fl) and the same time intervals (Tl , T2), previously used in accordance with the watering method according to the invention which has supplied a 95% efficiency.

The data obtained is reported in following table 2.

Table 2

Figures 8a, 8b and 8c give graphic evidence that the data in table 2 illustrating the efficiency of the automatic watering method according to the invention as a function of the percentage variation, respectively, of the second and third numerical coefficient ( 2 and K3), respectively, of the second and third measuring point (a, b) of a first reference system (SRI) (figure 8a); of the first numerical coefficient (Kl) relative to the first measuring point and of the first reference system (SRI ) (figure 8b), and the fourth and fifth numerical coefficient (K4 and K5) relative respectively to the fourth and fifth measuring point and of the first reference system (SRI ) (figure 8c). In these graphs, in the abscissa axis the percentage variations are indicated that are to be applied to the relative measuring point/s in order to obtain an efficiency of the watering system that is equal to the value indicated in the ordinates axis.

The following table 3 includes, for each measuring point, the intervals of the value or values relating to efficiency. efficiency 50% efficiency 50% efficiency 70% efficiency 90% / M ⁱ _t ^t ea _s remenou _p n ^s

Value of the Value of the Value Value of the f ^fi C ^t oe ⁱ cen

coefficient coefficient of the coefficient coefficient

First (e) K l 1 0.44 - 1.54 0.63 - 1,37 0.84 - 1.18

Second (a) K2 2 1.2 - 2.88 1.52 - 2.64 1.82 - 2.32

Third (b) K3 2 1.2 - 2.88 1.52 - 2.64 1.82 - 2.32

Fourth (c) K4 0.5 0.27 - 0.70 0.36 - 0.63 0.44 - 0.56

Fifth (d) K5 0.5 0.27 - 0.70 0.36 - 0.63 0.44 - 0.56

Table 3

With reference to table 3, the values of the first, second, third, fourth and fifth numerical coefficient (Kl , K2, K3, K4, K5) as defined in claim 1 , correspond by 50% to the efficiency of the watering method of the invention.

Therefore an automatic watering method according to the invention is preferred, wherein:

- the first numerical coefficient (Kl) is a number comprised between 0.63 and 1.37;

preferably between 0.84 and 1 .18 and more preferably is about 1 ;

- the second numerical coefficient (K2) is a number comprised between 1.52 and 2.64; preferably between 1.82 and 2.32 and more preferably is about 2;

- the third numerical coefficient (K3) is a number comprised between 1.52 and 2.64; preferably between 1.82 and 2.32 and more preferably is about 2;

- the fourth numerical coefficient (K4) is a number comprised between 0.44 and 1.54; preferably between 0.36 and 0.63 and more preferably is about 0.5;

- the fifth numerical coefficient (K5) is a number comprised between 0.44 and 1.54; preferably between 0.6 and 0.63 and more preferably is about 0.5.

To define the minimum inclination of the green wall (10), and the relative support, defined in step A) of the method according to the invention an experimental structure (400) has been used, represented in figure 9, which enables inclining a green wall ( 10) with respect to a horizontal plane (401). The inclination of the green wall (10) with respect to the horizontal plane (401) has been modified at a regular cadence, so as to carry out the testing at various inclinations for at least 48 hours consecutively, while maintaining the other conditions of the method fixed (number of reference systems, parameters, numerical coefficients, distances of the watering device, etc.)- Figures 10A, 10B, I OC, 10D, 10E, 10E, 10F, 10G, 10H, 101 E10L, relate respectively to an inclination of 90°, 80°, 70°, 60°, 50°, 40°, 30°, 20° and 10° with respect to the horizontal plane (401). They illustrate the humidity at points of the green wall (10) according to the relative scale of figure 10M. These show that with an inclination of 90°, the watering method of the invention enables correct watering and that by reducing the inclination of the axis of the ordinates, the efficiency of the method becomes progressively more efficient from 80° towards 40°, reducing cases of dryness stress (denoted by non-filled circles (500)) in the top parts of the green wall (10) and in any case keeping the cases of stress from over-watering to a limit (denoted by filled circles (600)). On reducing the inclination from 40° towards 10°, the cases of dryness stress in the bottom part became more frequent, while in the top part of the green wall (10) cases of stress from excess of water begin to emerge. This is probably due to the fact that the watering liquid flows with greater difficulty at smaller inclinations. At inclination 0° the presence of dryness stress in the bottom part of the green wall 10 is total. In conditions of inclination at 0° and 10° there is a continuous dispensing of water and therefore a pooling and flooding situation in stressed zones.

Therefore step A) of predisposing of the green wall 10 of the method of the invention preferably includes supporting the green wall (10) at an inclination of at least 30° with respect to a horizontal plane and more preferably of at least 40°- 80°. As the majority of green walls have a relative vertical support, the preferable method is the one according to the invention in which step A) of predisposing the wall involves the support of the green wall (10) being inclined by about 90°.

Concerning step E) of defining the watering line 80, reference is made to figures 6 - 6H and 7. Figure 6 relates to a green wall ( 10) (height 150 cm and width 90 cm) having a single panel, which constitutes the support thereof, associated to a single reference system, having an origin situated in the centre of the green wall (10) and having a single watering line (80). The first measuring point (e): X = 0; Y = 0; the second measuring point (a): X = -25 cm; Y = -55 cm; - the third measuring point (b) X = 25 cm; Y = 55 cm; the fourth measuring point (c) X = - 25 cm; Y = -55 cm; and the fifth measuring point (b) X = 25 cm; Y = 55 cm. The watering line can be positioned in positions Di(a) - Dl(g), which are parallel to one another and spaced by 10 cm from one another. Position Dl (b) passes through the second and third measuring point (a, b) of the relative reference system. Position Di(a) is the only one arranged below the measuring points a, b. Figures 6A - 6G relate to the different distances Di(a) - D l (g), shown in figure 6, of the watering line (80) from the first and second measuring point a, b of the method of the invention. The figures illustrate the humidity at points of the ^" green wall (10) according to the relative scale of figure 10M. The numerical coefficients used are the following: Kl = 1 ; K2 = 2; K3 = 2; K4 = 0.5; K5 = 0.5. In order to define the distance limit of 25 cm relative to the definition of the watering line (80), various tests were carried out leaving all the parameters, factors etc. of the watering method of the invention unaltered, modifying only the position of the watering device. As can be observed, by positioning the watering line (80) below the second and third measuring point a, b (figure 6A), at those points a too-low humidity level is detected and therefore the watering liquid is continuously dispensed, determining both excessive consumption and a stress due to excessive humidity in the middle and lower part of the green wall 10, as well as leaving the top part of the green wall without watering. By positioning the watering line (80) in proximity or at the second and third measuring point a, b (figure 6B), a suitable degree of humidity is detected in the majority of the green wall (10), but the plants located in the upper first 10 cm of the green wall (10) tend to die from lack of water. It is however possible for the method of the invention to be actuated in which the watering line (80) is defined of a reference system at the relative second and third measuring point, both when there is a plurality of reference systems, one beneath another, and when there is a single reference system, taking care not to position plants in the top first 10 cm of the green wall 10.

Position Di(c) (figure 6C) seems to be the best-performing, on observing the data indicated in the graph of figure 7. In fact, in position Di(c) the total number of cases of stress is 7 (4 dryness - 3 flooding). By increasing the distance between the watering line (80) and the second and third measuring point, the total number of stress cases progressively increases, due only to the flooding stress while the dryness stress tends to slightly diminish. Based on the appearance of total points of stress with respect to the situation in which fewer are manifested (distance 10 cm, i.e. position Di(c)), it can be asserted that position Di(d) (figure 6D) at 20 cm distance increases cases of stress by 43% in a total of ten cases of stress (however within the 50% efficiency threshold of the watering method).

Therefore, in step E) of the method according to the invention, the determining of the watering line (80) must be at a maximum distance (Di) of lower than 25 cm, from the second and the third measuring point (a, b) of the relative reference system or passing through the second and third measuring points (a, b) of the relative reference system. Preferably, this distance is smaller than 20 cm and more preferably about 7 - 15 cm, advantageously 10 cm.

The automatic watering system of the invention enables actuating the automatic watering method of the invention. It comprises:

- at least a watering device, connectable to a source of watering liquid for distributing the watering liquid uniformly along a watering line (80), the watering device comprising relative regulating means

(which can comprise or be constituted by a solenoid valve) predisposed for regulating an inflow of a liquid to the watering device and a consequent draining thereof from the watering device;

- a first number (Ngr) of detecting groups, placeable in the green wall in a relative number (Nr) of horizontal lines of detecting groups and/or a relative number (Nc) of vertical columns of detecting groups, wherein: Ngr = Nr x Nc

where Ngr is a first number (Ngr) of detecting groups, Nr is equal to the number (Nr) of horizontal lines of detecting groups, and Nc is equal to the number (Nc) of vertical columns of detecting groups; wherein the detecting groups in turn comprise a second number (Nsu) of humidity sensors, positionable in the green wall (10) for detecting the humidity of the relative positioning point given by:

Nsu = 5 + (Nr-1) x 3 + (Nc -1) x 3 + (Nr-1) x (Nc-1) x 2

where Nsu represents the second number (Nsu) of humidity sensors; and Nr is equal to the number (Nr) of horizontal lines of detecting groups; and Nc is equal to the number (Nc) of vertical columns of detecting groups; wherein each detecting group included comprises a relative first, second, third, fourth and fifth humidity sensor, and wherein, when a plurality of detecting groups are included, each detecting group has two sensors, adjacent to one another, in common with a further adjacent detecting group;

wherein the watering system further comprises:

- an electronic control unit (which can comprise or be constituted by an electronic control unit) predisposed for associating to each detecting group a relative watering device and the relative first, second, third, fourth and fifth humidity sensors; the electronic control unit being further predisposed for acquiring: a numerical term ( 0), a first, a second, a third, a fourth and a fifth numerical coefficient (Kl , K2, K3, K4, K5); and a first reference humidity parameter (PI ), which is relative to a condition of sufficient hydration of the green wall ( 10); proportional to a predefined first reference electrical potential (Vs); and given by:

PI = Fl x Vs

where:

PI represents the first reference humidity parameter (P I );

Fl is a first predetermined numerical factor of multiplication that is different to zero; and

Vs is the first reference electrical potential (Vs); in which

the electronic control unit is further connectable to all the humidity sensors included, once positioned in the green wall (10), for acquiring, at predetermined intervals and/or continuously, for each detecting group included, a first, second, third, fourth and a fifth electrical potential value (VI , V2, V3, V4, and V5) detected, respectively, by the relative first, second, third, fourth and fifth humidity sensor; and the electronic control unit being configured for, having first acquired: the first reference humidity parameter (P I), the numerical term (K0), the first, second, third, fourth and fifth numerical coefficient (Kl, K2, K3, K4, K5) and, once detected for each detecting group, the first, second, third, fourth and fifth electrical potential value (V I , V2, V3, V4, and V5), calculating, for each detecting group, a numerical value (M) proportional to a sixth electrical potential (Vm), given by:

M = Ko (Kl x VI + K2 x V2 + K3 x V3 + K4 x V4 + K5 x V5) / 5

wherein:

KO is the numerical term that is different to zero; and

VI, V2, V3, V4, and V5 are respectively the relative first, second, third, fourth and fifth values of measured electrical potential (V I , V2, V3, V4, V5);

Kl , K2, K3, K4, and K5 are respectively the relative first, second, third, fourth and fifth acquired numerical coefficients; the value of the sixth electrical potential (Vm) being given by:

Vm = (Kl x VI + K2 x V2 + K3 x V3 + K4 x V4 + K5 x V5) / 5

wherein

Vm represents the sixth electrical potential (Vm) and VI, V2, V3, V4, V5, Kl, K2, K3, K4, and K5 are defined as above;

the electronic control unit being further predisposed for comparing the absolute value of each numerical value ( ) calculated with the absolute value of the first reference humidity parameter (PI) for:

- when the absolute value of the numerical value (M) is lower than the absolute value of the first reference humidity parameter (PI ), commanding the regulating means of the watering device associated to the relative detecting group to open for a predetermined first time interval (Tl), and allowing a second predetermined time interval (T2) (preferably higher than the first time interval (Tl )) to pass before newly carrying out the calculation of the numerical value (M) and the comparison of the absolute value thereof with the absolute value of the first reference parameter (PI) of humidity.

It is clear that: once the first number (Nsr) of reference systems is defined, the second number (Ns) of measuring points of steps B, C of the watering method according to the invention; and once the electronic control unit has acquired the first reference parameter (PI); a number (Ngr) of detecting groups equal to the first number (Nsr) of reference systems; a second number (Nsu) of humidity sensors equal to the second number (Ns) of measuring points, the numerical term (KO), and the first, second, third, fourth, and fifth numerical coefficient, (K l , K2, K3, K4, K5) and has associated to each detecting group a relative watering device, it is able to actuate the remaining steps from F) to I) of the method.

As it is indispensable for the numerical value (M) to be proportional to the sixth electrical potential (Vm), it is sufficient for the numerical term (KO) to be different to zero, it can be 1 when the numerical value (M) is to be expressed in volts. When, on the other hand, the numerical value is to be expressed in amperes or percentage of humidity, and the sensor has a calibration curve which is a straight line, the value of the numerical term (KO) will be easy to determine by a skilled person by measuring the potential in a same point with a first type of sensor which directly measures the potential and a second type of sensor which measures the electrical current or the percentage of humidity read and dividing the electric current read or the percentage of humidity read by the potential read. Alternatively the value of the numerical term (KO) is determinable by the calibration curves of the sensor percentage of humidity in function of /potential or current in function of potential. The skilled person is able also to determine the value of Vs, for example by measuring, with a humidity sensor, the potential of a vase in which the same soil is used as that for the green wall, in which the same type of plant to be planted in the green wall is planted and in which there is a hydration condition that is sufficient for the cultivation of the plant in the soil.

The determination of the first number (Nsr) of reference systems (which is equal to the number (Ngr) of detecting groups of the system according to the invention) can easily be carried out by the skilled person, taking into account the dimensions of the green wall and the coordinates at which the reference points will be associated. It is in fact possible to calculate the minimum and maximum space that a reference system can occupy and thus determine the maximum and minimum number of the reference systems associable to the green wall. Any number comprised between the minimum number and the maximum number is usable for actuating the invention.

The detecting and/or acquiring of the first, second, third, fourth and fifth electrical potential value (VI , V2, V3, V4 and V5) is substantially contemporaneous and is preferably contemporaneous. Each of the watering devices of the system can comprise a hydraulic tube in which a plurality of holes is fashioned, aligned along the watering line, preferably substantially straight, with the aim of uniformly watering the green wall (10) along the line. The watering devices can be constituted by driplines. The watering devices can be connected to the aqueduct, or to a storage tank of the watering liquid. In an embodiment of the system of the invention it comprises the tank and pumping means for supplying the liquid to the watering devices.

When the green wall ( 10) has a height such as to justify the defining of two reference systems, step B) of the method of the invention can comprise a definition of at least an upper reference system (SRI) and a lower reference system (SR2) (see figure 4), wherein:

- the lower left quadrant of the upper reference system is partly superposed on the upper left quadrant of the lower reference system;

- the lower right quadrant of the upper reference system is partly superposed on the upper right quadrant of the lower reference system;

and wherein the step D) of associating the lower reference system with the relative measuring points is such that:

- the fourth and the fifth measuring point (c, d) of the upper reference system (SRI) coincide, respectively, with the second and the third measuring point (c, d) of the lower reference system (c, d). This defines the position of the first measuring point and consequently also the fourth and fifth measuring point and since the second and third measuring point must be positioned, with respect to the first measuring point, within the intervals of coordinates defined in the method according to the invention, the same can be stated for the fourth and the fifth measuring point.

When the green wall ( 10) has a width such as to justify the defining of two reference systems, step B) of the method of the invention can comprise a definition of at least a left reference system (SRI) and a right reference system (SR3) (see figure 4), wherein:

- the upper right quadrant of the left reference system is partly superposed on the upper left quadrant of the right reference system;

- the lower right quadrant of the left reference system is partly superposed on the lower left quadrant of the right reference system;

and wherein step D) of associating the right reference system with the relative measuring points includes:

- the third and the fifth measuring point (b, d) of the left reference system coincide, respectively, with the second and the fourth measuring point (b, d) of the right reference system. In this case too, the definition of the second and third measuring point defines the position of the remaining measuring points of the same reference system.

With the aim of further minimising the dryness stress, an automatic watering method according to the invention is preferred, wherein the step H) of comparison further includes, when the absolute value of the numerical value (M) is equal to or greater than the absolute value of the first reference parameter of humidity (P I), comparing: the absolute value of each result (S) of a series of multiplications of the numerical term ( 0); with, respectively, the first, the second, the third, the fourth and the fifth relative measured value of electrical potential (V I , V2, V3, V4, V5); with the absolute value of a second reference humidity parameter (P2) being: relative to a condition of insufficient hydration of the green wall (10); proportional to a predefined second reference electrical potential (Vd); and given by:

P2 = F2 x Vd

wherein:

P2 represents the second reference humidity parameter (P2) and has an absolute value that is lower than the absolute value of the first reference humidity parameter (P I):

F2 is a second predetermined numerical factor of multiplication that is different to zero; and

Vd represents the second reference electrical potential (Vd) and has an absolute value that is lower than the absolute value of the first reference electrical potential (Vs); for when at least an absolute value of the results (S) of the series of multiplications is lower than or equal to the absolute value of the second reference humidity parameter (P2), homogeneously distributing a watering liquid along the relative watering line (80) for a predetermined third time interval (T3), and leaving a predetermined fourth time interval (T4) to pass. The fourth time interval (T4) is preferably greater than the second time interval (T2).

Obviously the second reference parameter (P2) is lower than the first reference parameter (PI), and represents a parameter relative to the state of humidity such that in a determined green wall (10) the relative plants begin to suffer from dryness stress. When the second reference parameter (P2) is expressed in terms of potential difference, the second factor of multiplication (F2) will be one. In a like way to the first reference parameter (PI ), (P2) also must be determined by a operator in the sector in consideration of the characteristics of the substrate and the plants present in the green wall (10). For example bushy plants or ornamental plates that survive in dry environments will have a second reference parameter (P2), lower than ornamental plants that do not survive dryness stress.

Likewise it is preferable that the automatic watering system of the invention includes the electronic control unit being further predisposed:

- for acquiring a second reference humidity parameter (P2) that is relative to a condition of insufficient hydration of the green wall (10); proportional to a predefined second reference electrical potential (Vd); and given by:

P2 = F2 x Vd

wherein:

P2 represents the second reference humidity parameter (P2) and has an absolute value that is lower than the absolute value of the first reference humidity parameter (PI):

F2 is a second predetermined numerical factor of multiplication that is different to zero; and

Vd represents the second reference electrical potential (Vd) and has an absolute value that is lower than the absolute value of the first reference electrical potential (Vs);

- for, when the absolute value of the numerical value (M) is equal to or greater than the absolute value of the first reference humidity parameter (PI), comparing, for each included reference system; the absolute value of each result (S) of a series of multiplications of the numerical term (K0); with, respectively, the first, the second, the second, the third, the fourth and the fifth relative value of measured electrical potential (V I , V2, V3, V4, and V5) with the absolute value of the second reference humidity parameter (P2); and,

- for, when at least an absolute value of the results (S) of the series of multiplications is lower than or equal to the absolute value of the second reference humidity parameter (P2), commanding the regulating means of the watering device associated to the relative detecting group to open for a predetermined third time interval (T3), and allowing a predetermined fourth time interval (T4) to pass before newly carrying out the calculation of the numerical value (M) and the comparison of the absolute value of the numerical value (M) with the absolute value of the first reference humidity parameter (P I).

In order also to reduce flooding stresses, as well as dryness stresses, the step H) of comparison preferably further includes, when at least an absolute value of the products (S) of the series of multiplications is greater than the absolute value of the second reference humidity parameter (P2), comparing each absolute value of the products (S), which is greater than the second reference humidity parameter (P2); with the absolute value of a third reference humidity parameter (P3), the third reference humidity parameter being: relative to a condition of excessive humidity of the green wall (10); proportional to a predefined third reference electrical potential (Vw); and given by:

P3 = F3 x Vw

wherein:

P3 represents the third reference humidity parameter (P3) and has an absolute value that is greater than the absolute value of the first reference humidity parameter (P I);

F3 is a third numerical factor of multiplication different to zero; and

Vw is the third reference electrical potential (Vw) and has an absolute value that is greater than the absolute value of the first reference electrical potential (Vs);

for:

- when the at least an absolute value of the products (S), which is greater than the second reference humidity parameter (P2), is lower than the third reference humidity parameter (P3), allowing a predetermined fifth time interval (T5) to pass;

- when at least an absolute value of the products (S), which is greater than the second reference humidity parameter (P2), is equal to or greater than the third reference humidity parameter (P3), allowing a predetermined sixth time interval (T6) to pass, greater than the fifth time interval (T5) and greater than the sum of the first and second time intervals (Tl, T2).

The fifth time interval (T5) is preferably greater than the second time interval (T2) and more preferably is equal to the sum of the first and second time interval .

In a like way to the second reference parameter (PI), (P2), the third reference parameter must also be determined by an operator on the basis of the characteristics of the rooting substrate and the plants present in the green wall (10). For example, if some varieties of plants cannot survive in situations of high levels of humidity in the soil, the flooding limit will be lower than with other varieties. An example of an algorithm usable for actuating the method is illustrated in figure 1 1 , in which the numerical term O is 1.

When the third reference parameter (P3) is expressed in terms of potential difference, the third factor of multiplication (F3) will be one. As can be seen from the calibration straight line of figure 1 , the first, second and third factor of multiplication (Fl , F2 and F3) might not coincide with one another. In fact, in this case the calibration curve will be a straight line. Should the first, second and third reference parameter (P I , P2, P3) in percentage of humidity or amperes, the values of the first, second and third factor of multiplication (Fl , F2 and F3) can be easily determined by the skills person in the sector from the calibration curves of potential/intensity of current or potential/percentage of humidity of the sensors used.

Likewise it is preferable that the electronic control unit of the watering system of the invention is further predisposed:

- for acquiring a third reference humidity parameter (P3) which is: relative to a condition of excessive humidity of the green wall (10); proportional to a predefined third reference electrical potential (Vw) and given by:

P3 = F3 x Vw

wherein:

P3 represents the third reference humidity parameter (P3) and has an absolute value that is greater than the absolute value of the first reference humidity parameter (PI);

F3 is a third numerical factor of multiplication different to zero; and

Vw is the third reference electrical potential (Vw) and has an absolute value that is greater than the absolute value of the first reference electrical potential (Vs), for:

- when at least an absolute value of the products (S) of the series of multiplications is greater than the absolute value of the second reference humidity parameter (P2), comparing each absolute value of the products (S), which is greater than the second reference humidity parameter (P2); with the absolute value of a third reference humidity parameter (P3):

- when the at least an absolute value of the products (S), which is greater than the second reference humidity parameter (P2), is lower than the third reference humidity parameter (P3), waiting for a predetermined fifth time interval (T5), preferably equal to the second time interval, before newly carrying out the calculation of the numerical value (M) and the comparison of the absolute value of the numerical value (M) with the absolute value of the first reference humidity parameter (PI);

for, when at least an absolute value of the products (S), which is greater than the second reference humidity parameter (P2), is equal to or greater than the third reference humidity parameter (P3), allowing a predetermined sixth time interval (T6) to pass, greater than the fifth time interval (T5) and greater than the sum of the first and second time intervals (Tl, T2), before newly carrying out the calculation of the numerical value (M) and the comparison of the absolute value thereof with the absolute value of the first reference humidity parameter (PI).

In an especially preferred embodiment of the automatic watering system of the invention, the system comprises signalling means, and the electronic control unit is predisposed for activating the signalling means for signalling a corresponding alarm when at least an absolute value of the results (S) of the series of multiplications is lower than or equal to the absolute value of the second reference humidity parameter (P2); and/or when the at least an absolute value of the products (S), which is greater than the second reference humidity parameter (P2), is equal to or greater than the third reference humidity parameter (P3). The signalling means can comprise a warning light, or a sound signal or more preferably means for sending a radio, digital, satellite or GSM mobile telephone signal to the receiving device, which can be constituted by a personal computer, a mobile telephone or a tablet predisposed for receiving the signal and warning the user of its having been received.

Obviously it is particularly preferable to have a green wall/automatic watering system assembly comprising:

- a green wall (10) having a relative substantially planar support inclined by at least 25° with respect to a horizontal plane; the support being constituted by one or more panels for green walls, fixed to one another, the extension of which is substantially planar, each panel for green walls comprising a frame, a relative containing structure, permeable to water, fixed to the frame and defining a plurality of housings containing a rooting substrate;

- an automatic watering system according to the invention, wherein each detecting group included in the watering system is associated to a different reference system as defined in the defining step B) of the method according to the invention, wherein the first, second, third, fourth and fifth humidity sensor of each detecting group included in the system are positioned in the green wall (10) in the relative rooting substrate, respectively at the first, second, third, fourth and fifth measuring point of the reference system to which it is associated, as defined in step D) of the method according to invention of association of each reference system of the relative measuring points, and wherein each watering device included is arranged so as to distribute the watering liquid along a watering line (80) as defined in the defining step E) of the method according to claim 1. It is understood that the above has been described by way of non-limiting example. Any variants of a practical-applicational nature are understood to fall within the protective scope of the invention as described in the foregoing and as claimed in the following.