Installing Automatic Irrigation: A Geneva Guide

Installing automatic irrigation means dividing the garden into zones according to their water needs, burying the pipework, then handing control to a controller linked to solenoid valves. The best time to lay the pipes is before the beds and lawn are created, while the soil is still open. This guide covers the steps, the equipment choices and the upkeep to plan for, from lawn to hedges, right through to winterising.

Start from the needs: divide the garden into zones

A garden does not drink the same way everywhere. A lawn needs regular, evenly spread watering, a shrub bed appreciates a slow supply at the base, a young hedge needs targeted water, and pots on a terrace dry out very quickly. A good system respects these differences by creating several zones, each with its own type of watering and its own schedule.

Before buying anything, take stock of the site:

• the lawn areas, with their shape (square, narrow, irregular);
• the beds, hedges and individual trees;
• the pots, planters and window boxes, especially on terraces;
• the exposure of each part: full sun, partial shade, sheltered by a wall;
• the available water point and its location.

This simple mapping, even drawn by hand, forms the basis of the installation plan. It also helps you avoid the classic trap: mixing plants with opposite needs on the same line, which ends up drowning some to satisfy others.

Choosing the right equipment for each zone

Lawn: spray heads or rotors

For a lawn, pop-up sprinklers are used, which hide in the ground when not in use. There are two families:

• Spray heads (or diffusers) suit small areas and narrow or cut-up shapes. They water over a short range with a fairly fine spray.
• Rotors cover larger areas, with a longer range. They are suited to open villa or condominium lawns.

The choice depends on the size of the zone, but also on the available pressure. The aim is even watering, with no waterlogged patches or dry strips. To prepare the ground properly, see also our page on lawn mowing and care.

Beds and hedges: drip irrigation

For beds, hedges and shrubs, drip irrigation is the most economical solution. Water is delivered directly to the base of the plants, slowly, without wetting the foliage or the surrounding soil. This limits evaporation and the growth of weeds. It is installed either on the surface under mulch, or slightly buried.

Pots and planters

Pots are connected by small drip lines, with one emitter per container. This is the zone that dries out fastest in summer: it deserves a separate circuit, programmed more often but for short durations.

The components that make the system work

An automatic irrigation system relies on a few components working together.

The rain or moisture sensor deserves particular attention: without it, the system keeps watering during a storm. With it, the system adapts to the weather and avoids waste.

Mains or tank

The supply most often comes from the mains. A rainwater harvesting tank is an attractive alternative for watering without drawing on the mains, but you must check the flow and pressure provided by the pump. To think it through, our guide to rainwater management in the garden details the storage options.

Laying the pipes at the right time

The best time to install automatic irrigation is when the garden is being created. Trenches are dug without damaging any planting, the pipes are buried before the beds and lawn, and the finishing work (seeding, turf rolls, planting) is then done on ground that is already equipped. If you are starting a full project, see the garden creation page to coordinate the stages.

In an existing garden, installation is still possible, but it requires trenches across the lawn and between plantings, followed by reinstatement. It can be done, it is simply more visible.

The main stages of a careful installation:

1. site survey and zone plan;
2. choice of the connection point and the position of the solenoid valves (in an accessible valve box);
3. digging the trenches and laying the pipes;
4. fitting the sprinklers and drip lines;
5. dry run, adjusting the range and arcs of each sprinkler;
6. initial programming and fitting the sensor;
7. backfilling, then seeding or planting.

Adjusting, saving water and maintaining

A correct installation is not enough: the settings make all the difference. A few principles to remember:

• water early in the morning, when the wind is light and evaporation is limited;
• prefer less frequent but deeper watering for the lawn, which develops stronger roots as a result;
• adapt the programming to the season: a July setting is nothing like an April or September one;
• check that the sprinklers wet neither the walls, nor the paths, nor the street;
• comply with any watering restrictions imposed during a drought.

Winterising and restarting

Before the first frosts, the pipes must be drained or purged: water freezing inside a pipe can make it burst. You shut off the supply, empty the circuit, protect exposed components, then switch the controller off. In spring, you reintroduce the water gradually, check each zone, clean the filters and replace anything damaged.

A full annual check (blocked or misaligned sprinklers, leaks, clogged emitters, controller battery) keeps the system efficient. For a garden that is generally light on time, also read our guide to the low-maintenance garden. Full details of the service are on the automatic irrigation page.

The Geneva context

The Lake Geneva climate alternates summers that can be hot and dry with sometimes violent storms: a well-tuned system must therefore supply water in dry spells without adding more after a downpour, hence the value of the rain sensor. The bise, a frequent wind in the Geneva basin, carries water from long-range sprinklers off course; it is best to choose calm times, early in the morning, and larger droplets to limit drift.

As for the soil, the clay soils common in the canton hold water and become waterlogged quickly: slow, spaced-out watering is better than one large application, which runs off or stagnates. On sloping ground, run-off means shorter durations and cycles split into several parts. Finally, watering restrictions may be imposed during a drought: check with your commune before the hot season.

Depending on your area, see for example the pages landscaper in Cologny, landscaper in Veyrier or landscaper in Carouge.

Entrusting the project to a landscaper

Automatic irrigation is sized on site: pressure, surfaces, slope, exposure. Once you describe your project, a qualified landscaper contacts you within 24 hours, visits the site and prepares a detailed quote, free of charge and without obligation. You can request a quote in a few minutes.

Frequently asked questions

Can automatic irrigation be installed in a garden that is already landscaped?

Yes. You simply need to open trenches across the lawn and beds, then reinstate the surfaces. It is more visible than during a garden creation, but entirely feasible with good preparation.

Does automatic irrigation need draining every winter?

Yes, before the first frosts. Draining or purging the pipes prevents them from bursting under the effect of frozen water. The system is restarted in spring, with a check of each zone.

Is drip irrigation suitable for lawns?

No, it is designed for beds, hedges, shrubs and pots. For grass, spray heads or rotors are used, which spread the water over the whole surface.

What is the rain or moisture sensor for?

It stops the controller from watering when rain or soil moisture is sufficient. It prevents wasted water and overwatering, which weakens plants.

Can I water with harvested rainwater?

It is possible with a tank connected to the system, provided you have a pump suited to the flow and pressure required. You should also plan a back-up supply from the mains for prolonged dry spells.