Much of the water applied to lawns and gardens is never absorbed by plants. The greatest waste of water results from applying it too rapidly or too often. Water applied too rapidly is lost as runoff, which may carry polluting fertilizers and pesticides to streams and lakes. Water evaporates when applied to bare, unmulched soil, or in the hot afternoon.
- Water thoroughly, but only as needed. Generally, water turf weekly and water trees, shrubs, and ground cover monthly.
- Water early in the morning to prevent diseases and to minimize evaporation.
- Use drip irrigation where possible to minimize evaporation.
- Avoid wasting water on sidewalks and other paved areas. Also, try to keep water from running off your yard.
- If you use a sprinkler, consider buying one that will spray large droplets, not a fine mist that can evaporate before it hits the ground.
The key to watering lawns is to apply the water infrequently, yet thoroughly. This creates a deep, well-rooted lawn that efficiently uses water stored in the soil. Different soil types respond differently, so know your soil type and water accordingly.
Watering Trees, Shrubs, and Ground Covers
As with lawns, apply water infrequently yet thoroughly. In the absence of rain, most trees, shrubs, and ground covers benefit from a thorough monthly watering during the growing season. Move a slow-running hose from point to point along the dripline of each plant until each area becomes saturated to a depth of 8 to 10 inches.
Drip irrigation is more efficient than using a sprinkler. Drip irrigation slowly applies water to the soil. The water flows under low pressure through emitters, bubblers, or spray heads placed at each plant. Water applied by drip irrigation has little chance of waste through evaporation or runoff.
Make sure that sprinkler heads are properly adjusted to avoid watering sidewalks and driveways. A sprinkler head should spray large droplets of water instead of a fog of fine mist, which wastes water by evaporation and wind drift. Water early in the morning when possible. Avoid watering from mid-morning to late afternoon – you can lose one-third of your water to evaporation. Avoid watering in the evening because lawns and plants left wet overnight are more prone to disease.