Balconies and terraces, the principle of installation for plants in pots

An automatic watering system for a terrace is very simple to install. All you need is a simple tap. A 220 volt power supply is not necessary.

Let's get rid of the idea that such an installation is only useful during your absence, for vacations: like any watering system, it is a comfort that can be used most of the year, and that allows to save water.

Most of the big DIY stores sell all the material you will need. It is very easy to install, the fittings being, for the most part, to be fitted without tools.

Principle of installation of the system

• At the beginning, a tap on the terrace.
• We place on it a "double outlet" which will allow to multiply by 2 the fittings.
• On the first one, we screw a battery programmer (use good quality alkaline batteries: Varta or Duracell for example).
• The second outlet will remain free and autonomous in order to easily wash hands, fill a bucket...
• After this programmer, connected by a piece of garden hose, come the filter and the regulator.
• The filter prevents particles from blocking the small sprinklers placed in the pots (or planters).
• The pressure reducer is used to lower the pressure and regulate it. All the rest of the installation works in low pressure: from 1,5 to 2,5 bars.
• Since the installation is now in low pressure, it is necessary to unroll polyethylene pipe of diameter 13x16mm (in the Garden department, in GSB).
• For the terraces made on slabs, it is possible to pass this pipe underneath: the discretion of the installation is then total.
• At the end of the pipe, put a small stop valve rather than a plug, this allows to drain the pipe before winter: once the pipe is emptied of its water, the major part of the installation remains in place outside.
• From this main 13x16 pipe, we will create many branches, to go up in each pot, with small 4mm (or 4,6mm) pipe. This pipe should not be used as the main supply; we cut short lengths of it (from 1 to 5 meters) which will be connected to the 13x16 pipe.
• Finally, at the end of the small pipe, a dripper or a micro-sprinkler (usually reserved for very large containers) is installed. The installation must include one or the other. I strongly advise against mixing these two sprinklers, which are very different in terms of the amount of water they deliver.
• The only thing left to do is to fix the dripper with a small spike (or ground spike) so that it does not touch the ground directly but is slightly raised.

Tips for use

Set the timer for watering late in the evening, ideally at night, or early in the morning. If the trays can't hold water, why not do three short waterings...? With a good battery, you can water several times a night, for more than six months, without ever changing the battery.

But before winter, bring in the timer, remove the battery and put in a new one the following year.

With a simple installation like this one, you save time, peace of mind, you use less water than with your watering can, with a much better result.

Make several watering networks

You now have the technical study in hand in order to realize the underground watering of your garden. Therefore, you will probably have to make several watering networks.

Indeed, from a single source of water supply (tap, pump ...), the flow (volume of water) and pressure (speed of water circulation) will not be sufficient to operate all the sprinklers in your garden at once.

It is therefore necessary to distribute this power in several successive stages, which will water one after the other: in cascade. When the first part will have finished its cycle, the second part will start, then at the end of the second cycle the third...etc.

To do this, we must create an important part of any underground watering installation: the solenoid valve manifold [see photo above ].

This manifold (also called "clarinet") is composed of various parts :

• the single water inlet pipe, coming from your pump or your faucet, with its fitting
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• a shut-off valve (with a small bleeder) to isolate the watering from the rest of the domestic supply, for example in case of repairs on the installation. This valve can be placed well before on the water supply pipe, but regardless of its location, it is essential. That is why it can be found at the entrance to the collector, but often it is located in the basement, in the garage ...
• Union fittings: these have various shapes (elbow, cross, tee...). For a few years, they are now easily dismountable and do not require any sealing product such as Teflon. They allow all kinds of assemblies, depending on the number of networks to be made and the desired configuration. The main advantage of these fittings is the fact that disassembly for repair is significantly simplified.
• The solenoid valves: this is the nerve centre of the installation. These are the parts that open and close on command from the programmer.
• Since they will operate in cascade, the number of solenoid valves is not limited. Logically, you should install as many as you need.
• You must connect them and the pipes that go out into your garden.
• The whole thing will be placed outside, under the ground level, in a manhole which is provided with a green cover: this one will be discreet, even implanted in your lawn
• Finally, it remains to install a multi-strand electrical cable near the collector, to connect the solenoid valves to the programmer in a watertight manner.

As a finishing touch, you can put a little gravel at the bottom of the manhole, this allows the water to drain.

Now you can water your whole garden with one hose, but in several steps: the programmer and the solenoid valves work for you at night.

Automatic watering

With the arrival of the vacations, you start to wonder how you will find your garden and your indoor plants when you return. You think of your family, neighbors or close friends to come and visit your garden in your absence but they are not always available and you would rather not bother them with your garden.

There are several solutions. From the most rudimentary to the most sophisticated and this going with that from the most economical to the most expensive, you will find a solution to your expectations and your budget.

The D system

The economic solution par excellence and within the reach of everyone. It is not a question of cleaning up the garbage in your neighborhood but simply keeping your empty plastic bottles in order to reuse them as water reserves.

The principle consists in placing bottles filled with water upside down, with the neck in the ground. The watering is then done naturally by gravitation according to the humidity of the ground. All sizes are allowed: 0,5l - 1l - 1,5l - 2l - 5l.

Ideal solution for outdoor use, for your vegetable garden and your flower beds. 2.

Pots or tubs with reservoir

We will not dwell on this solution which is ideal indoors but whose aesthetics are sometimes questionable.

Outside, it finds its limits beyond 15 days of absence. Ideal for your geraniums of balconies, terraces, your jardinières of ornamental plants.

Carrots

It is not a question there of sowing rows of carrots but of setting up water diffusers whose shape evokes the vegetable of the same name. They are connected to a reservoir that supplies them with the necessary water.

This water tank can be any container: a bowl, a plastic bucket,... The volume must be in relation with the duration, moreover cover it to avoid too much evaporation.

Ideal: indoors and outdoors, for plants in isolated pots that should be grouped around your water supply. It is also suitable for planters without or with a reservoir (to which it can be added).

Tip: when outside, place a second hanging planter opposite your hanging planters and fill it with water. Your balcony will stay in bloom in your absence.

Watering systems

Automatic watering systems allow you greater flexibility in managing your watering with the possibility of

• adapt the flow rates according to your plants
• program the frequency and duration of watering

However, they need to be installed 15 days before your departure in order to check that they are working properly and that the volume of water poured is adequate for the needs of the plants.

This solution is the most expensive. However, when considered in the context of daily watering of your garden, it becomes by far the most interesting.

The watering system with a pump

The watering system consists of

• a transformer with a built-in programmer
• a low voltage pump immersed in a water tank
• a network of plastic pipes
• micro-drippers (several flow rates are available)

The capacity of the water tank is to be sized according to the water needs in your absence:

Volume of the tank = Watering frequency x Flow rate of the micro-dripter x Duration of watering x Number of micro-drippers x Duration of your stay

Ideal: indoors if you do not want to move your plants. Advice: don't hesitate to place larger sub-pots or even to put pot covers for the eventual overflow.

The watering system connected to the faucet

The watering system consists of

• a programmer screwed to your water tap: the price varies proportionally to the possibilities offered
• a pressure reducer to limit the pressure to 1.5 bar
• a network of plastic pipes of several diameters.
• cross, tee and Y fittings
• micro drippers (several flow rates are available) - various micro sprinklers:
• for trays ......................... to 360º.
• stopcocks to isolate your watering installation by zone. This will allow you to intervene on a zone of your garden while maintaining the watering of the other zones. Recommended for isolating the circuit dedicated to planters and pots during their wintering period.
• Flow regulators

To create your network without too much pressure loss, start with the primary network composed of large pipes. It is the backbone of your network and guarantees sufficient pressure in the most remote areas. Consequently, it must cross all the areas you wish to water.

Note that in the case of very remote areas, it is advisable to provide a service to the primary network(s) by buried reinforced pipes. The pressure reduction will then only take place at the connection with the primary network.

Then install the secondary network made up of thin pipes, a real local service for your different plants.

Ideal: outdoors, if you plan to use it as a year-round watering solution for your garden.

Advice: install your programmer on an outdoor faucet to prevent flooding in the event of a hose rupture or if a connection breaks.

Otherwise, water your garden and your indoor plants before you leave, nature will do the rest.

Drip irrigation

Economical and ecological, drip irrigation is the solution of choice in the garden and even on a balcony. Coupled with a programmer, you will no longer have to worry about watering your plants so that they are beautiful and healthy!

What is drip irrigation?

• It is a low-pressure micro-irrigation system that starts with a simple water tap that feeds the main circuit consisting of a pressure reducer, a hose that carries the water to the plantations (diameter 16 to 25 mm), and then secondary circuits that can be made with thinner hoses (diameter 4 to 6 mm). The available hose lengths range from 5 to 100 m.
• Drip irrigation is usually coupled with a programmer that allows you to plan the watering times. The connected programmer offers even more freedom to the gardener.
• Note that there are watering kits that do not require a faucet or electricity. They are interesting in isolated areas or in the context of an unoccupied second home. They work from a rainwater collection tank, by gravity. The programmer is powered by batteries or even a small solar panel.

The dripper, the star of micro-irrigation

Watering each plant directly at its foot by drip is the goal of this micro-irrigation watering. To do this, drippers are placed on the pipes, with a fixed or adjustable flow rate, they allow you to irrigate each plant according to its needs by providing water progressively, drop after drop (from 0 to 20 liters per hour).

Note that the drippers can be placed directly on the first circuit if the watering plan is linear and/or on the secondary circuit.

From the simplest with a fixed flow rate to drippers whose flow rate can be adjusted by rotating the head, the choice is vast. The most fastidious will turn to professional solutions such as self-regulating drippers that compensate for a too low or too high pressure to deliver the required amount of water. These drippers will also solve the problem of a very sloping ground but be careful: often, they cannot be closed if a plant disappears unlike the adjustable drippers.

There are also built-in drippers for simplicity, but they do not allow the same creativity as a system where the gardener chooses to install his drippers according to the positioning of the plants already in place. Built-in drip lines have a spacing of 15, 30 or 50 cm, so it will be necessary that the garden is not yet planted or that the plants are exactly at these spacings for the system to be effective. However, this type of hose is easier to install and saves a lot of time.

What are the advantages of drip irrigation?

• This type of irrigation is very localized and ensures the preservation of water resources, the interest is both ecological and economic. Indeed, we count a saving of about 25 to 40% compared to a traditional watering for an efficiency 40 to 50% higher.
• The plants are watered at the right dose and in a regular way, which avoids the hydric shocks which weaken them in case of forgotten watering.
• The water is brought under low pressure to the feet of the plants and penetrates slowly towards the root system which benefits directly from it.
• The foliage is not watered, which avoids many cryptogamic diseases or leaf burns.
• The possibility of programming the watering offers a newfound freedom for the gardener who can finally go on vacation or take care of other activities.

How to install an efficient drip irrigation system?

Flow rate and pressure are the basic concepts of drip irrigation.

• Depending on the diameter of the hose, the flow rate will be more or less important. It is therefore crucial to calculate the necessary flow rate for the number of drippers installed and the length of the pipes.
• The flow rate of each dripper is given for a pressure of 1 bar (achievable thanks to the pressure reducer installed at the faucet outlet). For example, if you want to install 10 drippers with a flow rate of 2 l/h and 20 drippers with a flow rate of 4 l/h on your circuit you will need a total flow rate of 100 l/h. It is always better to limit yourself to a maximum of 50 drippers per circuit.
• A 16 mm diameter pipe will be chosen for a circuit of 50 to 100 m length, beyond that a 20 mm diameter pipe will be necessary so that the flow is always correct at the end of the circuit.
• Always differentiate between circuits with drippers and circuits with sprinklers. To do this, you can divide your irrigation plan into several circuits using directional elbows, bypass tees, plugs to complete a circuit...
• Don't forget to think about the solenoid valves needed to create several separate circuits. These solenoid valves, placed at the beginning of each circuit, are programmable. They work either under electrical tension via a programmer, or individually thanks to batteries. The solenoid valves allow you to operate each circuit independently.
• If your irrigation system has only one circuit, a timer will be installed just below the faucet to control the frequency, duration, and timing of watering automatically.

What is the best frequency to program a drip irrigation?

Watering should preferably be scheduled in the late evening after sunset so that evaporation is reduced and the plants get the most out of the water.

If each dripper corresponds to the real need of the plant, the watering can be started during one hour every evening in summer. In dry and hot weather, it can be extended by one hour. Only experimentation will help you decide on the duration and frequency, as each garden is exposed differently and exploited in different ways (presence or not of mulch, weeds...). It's up to you to learn how to dose, and to enjoy your tranquility!

Equipment for automatic watering

Automatic watering allows you to program a regulated irrigation according to the specific needs of the plants. It will also save you the chore of watering which can quickly become a hassle, especially in summer.

Automatic watering: what you need to know

The quality and diameter of the hoses chosen are essential parameters when installing an automatic watering system. Flexible or semi-rigid hoses must be able to withstand a pressure equal to or greater than 6 bars because they will be equipped with water intakes that will then carry the various types of sprinklers.

The hoses must be of very good quality in order to be assured of a long life, to resist to the climatic hazards and to the possible rodents.

In general, 25 mm diameter pipes will be sufficient unless your network is very long or your flow rate is enormous, in which case 32 mm diameter pipes should be preferred. The larger the diameter, the lower the risk of pressure drop at the end of the stroke.

The different types of sprinklers

Sprinklers are chosen according to the plants and their needs. Drippers are preferred for vegetable gardens or ornamental gardens because their flow rate can be adjusted individually according to the needs of the plants grown, while turbine, oscillating or rotating sprinklers will ensure the watering of lawns.

Please note: the two types of sprinklers cannot be installed in the same circuit because the flow rates and spans are not at all similar. It will be necessary to create two separate lines.

The various circuits

When your garden requires several circuits with different zones and different types of sprinklers, it is necessary to divide the automatic watering into several separate circuits. In this case, a selector switch with multiple outlets should be placed on the water supply valve. If you do not have a large flow rate, you will also need to install solenoid valves to trigger the circuits one after the other. There are two models: battery-operated (9 volts) or wired (powered by 24 volts). Remember to respect the direction of water flow when installing.

The programmer

The programmer is used, as its name indicates, to program the hours and duration of watering. It can be equipped with a humidity sensor or an electronic rain gauge that will allow the automatic watering to start if the soil is too dry or simply to stop if it rains enough.

The micro-sprinkler for your garden

The Micro Sprinkler is a watering system particularly adapted to large flower beds and rock gardens.

The Micro Aspersion produces a very fine rain that waters at low pressure (it does not damage the flowers, even fragile ones) and over different distances quite wide (1 to 3 meters radius depending on the brand).

This one is very easy to install since all the pipes are on the surface, with connectors to be plugged or screwed: many parts are common with a Drip system (see sheet: balconies and terraces). However, never mix micro-sprinklers with drippers on the same pipe.

So, a programmer on the faucet, a piece of garden hose with fittings, a filter + pressure reducer, PE hose with a diameter of 13x16, ground spikes to hold the hose in place, a small shut-off valve at the end of the hose that will allow for easy draining in the winter (since the hose is on the surface, it is not protected from the cold)

Once the main 13x16 pipe is in place, simply create branches on small pipe (4mm or 4.6mm) to a support.

At the top of this support, the micro-sprinkler is screwed or plugged in.

Note that the small tube branches should be relatively short (generally not more than 1 meter) and that between the support and the micro-sprinkler, it is often possible to place an extension (to raise the micro-sprinkler according to the vegetation) and a small regulating tap (to adjust the distance of the jet).

A micro-sprinkler is placed every 2 or 3 meters or so (depending on the technical characteristics): the jets must cross each other, as one sprinkler must always try to water its neighbor.

Even if they water at a pressure of a few bars in fine rain, the micro-sprinklers can have a large flow (up to 100 liters for some). It is therefore not possible to place too many of them on a single pipe.

The main technical advantages of micro-sprinklers are, if compared to drip irrigation:

• Excellent watering coverage over a large area (for a rock garden for example). The drip only waters a strip of land about 60cm wide.
• less hoses to pass through the beds, it facilitates the maintenance/planting and reduces the risks of breakage.
• in a caricatural way, where 50 drippers are needed to water a bed, we obtain a much better water distribution with only 5 sprinklers.
• the sprinklers, in height, do not get blocked, contrary to drippers which can end up being buried in the very dense massifs.
• it is easy to move a sprinkler since it is always in branch of the main pipe on a support planted in the ground. As a remark, I would indicate that the solution of putting the sprinklers directly in the 13x16 pipe is not qualitative in terms of watering and can, in some cases, be defective very quickly (from the second year).
• finally, the micro-sprinkler system is aesthetic when it works (editor's note: you will tell me that it must work around 2:00 am, and that the visual aspect is not essential at this hour ....)

All this being very easy to install, I wish you a "good installation".