Contents
Table of Contents
Installation of pop up sprinklers
Installing pop up sprinklers is the surest way to water a lawn evenly. Each head rises from the ground when the pump is activated, throws water in a circle, then retracts when the system is turned off. This guide covers the three decisions to settle first, the eleven installation steps, and how to run the system afterwards.
What pop up sprinklers do on a lawn
These heads stay hidden below the turf line while the system is off. When pressure arrives, the riser pushes the nozzle up so water is sprayed over the bed. When the pump stops, a spring returns the body flush with the ground. Typically the lawn stays mowable, and the head never blocks a mower blade.
Because the head sits in a pit, the piping, valves and wiring also go underground. Therefore the work is a short installation rather than a permanent change to your landscape. It also means the system must be planned before the grass is laid, or the lawn must be cut open and re-turfed afterwards.
Three decisions before you install pop up sprinklers
Quantity of water a lawn needs
Most lawns need about three centimetres of water per week, though some compounds differ. Sandy soils may require more water, while heavy soils require less. It is best to water deeply and infrequently on heavy soils, so that percolation rates are catered for. For the science behind that depth figure, see the FAO chapter on reference crop evapotranspiration, which is measured over a grass surface.
Appropriate time of lawn watering
Morning is the best time to irrigate your lawn. Midday watering, when the sun is high, should be avoided to prevent water loss by evaporation. However, watering in the evening raises the risk of disease, because grass stays damp all night. Those losses are mostly fungal.
Watering newly planted lawns
Newly planted lawns need more frequent irrigation than established ones. Depending on the weather, new lawns may need to be watered daily. Water enough to keep the soil moist, but not too wet. Instead, over-watering can wash seeds away, make them rot, cause disease, or slow the growth of grass.
What a lawn system of pop up sprinklers is made of
A lawn irrigation system has four parts: timers, valves, underground piping with its fittings, and the sprinkler heads. Each part has a job, and the layout of one governs the next. First, the timer decides when the pump runs. Then the valves decide which zone opens. Next, the piping carries that water below the surface, and the heads turn it into an even coverage pattern.
For a wider picture of overhead systems and how they are zoned, read the page on our sprinkler irrigation system before you buy anything.
Step-by-step installation of pop up sprinklers
- Level your lawn area first. This gives a plain, beautiful landscape once the lawn sprouts.
- Select a head based on yard size and shape. Take the running lengths of the lawn, then divide by the wetting radius of the head you can buy.
- Cut the ditches in which the piping will pass. Use spades, jembes, or any ground-breaking tool.
- Lay the underground pipe in a straight run. Take into consideration the position of every head.
- Cut the pipe at the exact position shown on your design, then install the head at that point.
- Turn on the pump to flush the main line. This removes debris that found its way into the pipe, then close the end with an end cap.
- Try to supply a uniform amount of water across the whole lawn. Monitor this by placing containers at various points beneath the spray pattern.
- Measure the water captured in each container. Therefore overlap the spray patterns until every part of the lawn receives a similar quantity.
- Program your timer to water in cycles. Heavy soils and slopes sometimes cannot absorb water fast enough. To prevent runoff, run several shorter periods with about an hour in between, so the water soaks in.
- Adjust the system to current weather. There is no point in watering during heavy rain, since soil can only absorb so much at once.
- Change your schedule with the season. A lawn needs less water during the rainy season than during the dry season.
Pop up sprinklers compared with other lawn watering methods
Overhead heads are not the only option for a green cover. The table below compares them with two methods we also supply. For a bed of shrubs or a greenhouse bench, water delivered to the root zone is usually the cheaper match, and the drip system page explains such a layout. Read the advantage of a drip irrigation system before you rule out buried lines.
| Method | Where the water goes | Best suited to | Main risk |
| Pop up heads | Over the leaves, onto the turf surface | Mown lawns and open ornamental beds | Evaporation when run at midday |
| Drip lines | Straight to the root zone, below the surface | Rows, hedges, greenhouse benches | Emitters clogging if the water is dirty |
| Rain guns | Thrown a long radius over a wide field | Large paddocks, pasture and fodder plots | Uneven edges on a small, shaped lawn |
On a large open field, a high-radius gun may suit the area better than buried heads. Check what a 100 meter rain gun costs before you commit to either layout.
Mistakes that stop pop up sprinklers from watering evenly
The most common failure is skipping the container test. Without it, dry patches are blamed on the head rather than on a gap between patterns. Similarly, some installers lay pipe without flushing the main line, so grit reaches the nozzle and blocks the riser.
Another mistake is sizing by guesswork. Because head spacing follows the wetting radius, a lawn measured by eye almost always ends up with too few heads. Finally, running the system at midday or late evening wastes water and invites fungal disease.
How to schedule the system through the season
Scheduling is where most of the water is saved. Water in the early morning, in shorter cycles rather than one long soak, so heavy soil absorbs what lands on it. Meanwhile, keep the weekly target near three centimetres, and let rain count against it. Consequently, a system that runs on a fixed timer all year will always use more than a lawn actually needs.
Frequently asked questions about pop up sprinklers
How many heads does a lawn need?
Take the running lengths of the lawn and divide them by the wetting radius of the head you have chosen. That gives the count, which you then space evenly along the pipe run.
Is a borehole required to run them?
No. The heads need pressure and flow, so a pump-fed tank or borehole supply will both work. Where water is the limiting factor, our page on borehole drilling in Kenya explains how supply is arranged.
Can the system be fitted to an established lawn?
Yes. The ditches are cut with spades and jembes, then closed behind the pipe. Expect to re-turf or re-sow the cut lines, since the trench crosses the sward.
Why do some patches stay dry?
Usually because the patterns do not overlap. Set containers beneath the spray, measure what each catches, then move or add heads until the readings match.
Should a new lawn be watered on the same schedule?
No. Newly planted grass needs more frequent irrigation, sometimes daily, kept moist rather than soaked. Over-watering washes seed away and encourages rot.
Do pop up heads stay visible?
Rarely. Each body retracts flush with the ground once the pump stops, which is why a mown lawn hides the whole system between cycles.
Where to buy pop up sprinklers in Kenya
Eunidrip Irrigation Systems supplies lawn heads, valves, timers and the underground pipe that feeds them. Our irrigation solutions page sets out the systems we supply, and it lists sprinkler layouts alongside the drip options. Call +254 728 163329 or +254 724 775516, or use the contact page, and ask for a layout drawn around your yard’s running lengths.