Drip irrigation is now widely used for watering trees and orchards because it applies water slowly and encourages plant growth. The changing water needs of the tree can be easily accommodated. Saplings can start with one or two emitters at the base of each tree, and additional emitters can be installed as the tree grows. Remember, when designing a drip irrigation system, design the system for the flow of water that will be required when the tree is fully mature.
There are four common methods to use drip irrigation for a tree or group of trees:
1) run laterals down a row of trees with emitters placed on the lateral line at the base of each tree;
2) run two lateral lines along the row of trees, about 3 feet on either side of the tree to encourage a more balanced root growth;
3) “tee off” each lateral line with a loop around each tree equal to approximately three fourths of the circumference of the tree’s canopy, and placing 3 emitters equally spaced on the loop;
4)in locations with sandy soil, mini-sprinklers or sprays are often used. One micro-sprinkler on a riser can cover the entire root zone of a tree