How should I water?

Trees vary with moisture requirements, but for established plantings, deep, infrequent watering is recommended. In most cases, an inch of water per week (rain plus irrigation) should be sufficient. Applying that inch of water in one deep watering will encourage deeper rooting, which leads to stronger, healthier plants. Watering once a week also fits well into most municipal water restrictions. Shallow, frequent watering, on the other hand, will lead to shallow root systems and high water loss through evaporation.

The best time of day to water is early morning before the temperatures begin to rise. This gives the plants a good supply of water to face hot days. Early morning also tends to be a time of lower winds and thus reduced evaporation. If watering cannot be done in the early morning, very late afternoon is also satisfactory. It is important to water early enough so that the leaves have time to dry before nightfall to avoid development of fungal diseases. If possible, choose watering methods that will not wet the leaves (such as soaker hoses) and thus allow for late evening watering.

Sprinklers are good all-round watering devices but they do tend to waste water and wet the leaves.

Root feeders are popular for watering trees and shrubs. These can be useful devices, but they must be used properly. The roots that are active in water uptake are not found near the trunk, but rather out at the dripline and beyond. Therefore, the root feeder should be used away from the trunk to be effective. Many people put the root feeder too deeply into the soil. Most of the roots in a tree or shrub’s root system will be in the upper 12-18 inches of soil. The root feeder should be inserted so that water is delivered to that area.

Soaker hoses have also favorite watering devices. Soaker hoses allow water to leak out gently over the entire length of the hose. The benefit to using these hoses is that the leaves are never wet, reducing the possibility of diseases. The water goes right to the root system where it is needed and very little is lost to evaporation. Soaker hoses must be left on for a length of time to water deeply. An inch of water penetrates about six inches in a clay soil. To check how it delivers to your soil: let your hose run for a while, then dig down with a trowel to see how deep the water went. If it is less than six inches, the hose needs to run longer.

----back to FAQ's---