Concepts of Irrigation Design
1. Irrigation systems are sunk below the landscape.
Generally, you’ll want to recess 3.5”-4” rigid PVC piping underneath your hardscaping (walkways, driveways, and patios), which you can later use to pull your irrigation lines through. (You’ll want to use a separate one for electrical lines). Make sure that all isolated planting beds have piping leading to them so you can water them.
2. Double the codes.
Many contractors will double the required size for PVC piping in case the site needs additional irrigation systems later—if, for example, the landscape expands.
3. Short watering intervals are best.
The ground has a saturation point, and once that’s reached, the rest of the water rolls right off the top. It’s far more effective to water your lawn for 15 minutes twice every other day than once for two hours. This is especially true when irrigating rooftop or balcony gardens. These types of planting beds will use a different, lightweight soil mixture that requires more water because of the adverse weather conditions.
4. The best time to water is in the early morning.
At 4 a.m., your irrigation system doesn’t interfere with the house water. This ensures that water pressure is not lost through showers, toilets and washing machines.
5. Check that you have adequate water pressure in the house.
You can put a gauge on the water faucet to check pressure. You should have between 50 and 60 psi.
6. Check for volume of water.
You should have at least a 1” line coming into the house from the water company. If you have less than 1” you may need a booster pump to increase water pressure.
7. Understand the soil conditions you have to work with.
Sandy, well-drained soil requires more water, while clay soil requires less. Talk to someone at your local nursery for more information on area soil needs.
8. Match your irrigation systems to your needs.
Pop-up irrigation heads in planting areas with high shrubs will help you avoid the maintenance of irrigation heads mounted on bars and fences. Drip systems can help bring water directly to plants and will help conserve water.
9. When irrigating a large garden area, consider installing a simple coupler as part of the system.
The coupler will allow you to quickly attach a garden hose to a water source when you are far away from the house faucet. By installing a quick coupler, you can easily attach a garden hose anywhere in the garden and wash down an area without storing lengths and lengths of hose.