Planning Tree Irrigation

When planning an irrigation system for trees, a common misconception is that tree roots will "grow toward water." Roots will not grow through dry soil.

Trees require water in a larger area to allow the roots to spread out and provide a sturdy base for the tree.

Young trees need enough drip emitters to cover the canopy from the tree trunk out to the ends of the branches.

Mature trees should have enough drip emitters surrounding it that 50 to 75 percent of the tree's canopy area should be wet.

If a tree is standing alone in a landscape, its demand for water increases as the tree and the roots grow. The wetting pattern must be increased at the same time. Roots only grow in soil that provides moisture and growth can be stunted if the roots can't find moisture as it tries to grow.

Common mistakes

The following mistakes are commonly made with drip irrigation for trees:

• Setting your irrigation clock for your tree to run the same as spray irrigation
• Mixing irrigation components
• Not using filters or pressure regulators
• Not property burying drip irrigation lines
• Applying too much gravel mulch before establishing wetting patterns
• Poor emitter placement which results in poor wetting patterns
• Not maintaining the drip irrigation system