How to Water Trees During a Drought
Trees suffer during periods of drought but are often overlooked until the damage becomes visible. Tree roots generally grow in the top 18-24” of soil so even large trees are subject to drought stress.
Trees will prefer to be watered more deeply rather than watered more often.
Whether during a severe drought or just abnormally dryer conditions, it is important to water slowly and deeply, allowing the water to penetrate the soil well into the root growing zone. Slow, steady applications of water are preferred over fast and high volumes of water. Always water more deeply rather than watering frequently.
You’ll want to make sure you are watering the entire root growing zone. For more mature trees the tree watering zone becomes extended far beyond the original planting hole, well past the drip line or canopy of the tree. One rule of thumb to determine the root zone is to care for an area two times as large as the drip zone or canopy of the tree.
The #1 Cause of New Tree Planting Failure Results from Poor Watering.
Improper watering leads to inadequate growth, poor health, and even death of your tree. A water stressed tree can weaken a tree’s natural defenses against pests and disease while a properly watered tree can enhance natural defenses. This is why proper tree watering is so vital to your trees success.
These failures can be attributed more often to infrequent watering as opposed to over or under watering. Therefore, we need to be smart about how we water newly planted trees.
The Science Behind Tree Watering for Success
To understand the watering needs of newly planted trees, we need to look at the relationship between water, soil and your tree. Understanding what takes place in your soil environment as well as within your tree is going to be crucial.
There are many types of soil, some better than others. A key difference between soil types is the availability of water within the soil. Generally, water is more available in sandy soils and becomes less available in clay soils. The higher the availability of water, the quicker water becomes unavailable as it drains through the soil. This is why some soils seem to dry quicker than others, causing them to require more frequent watering. It is important to begin to know your soil’s behaviors so that you know how you might be able to adjust this behavior, ensuring proper watering for your tree.
Ideally we are seeking to enhance drainage and available water for the longest period possible without over watering or under tree watering. To achieve this, soil amendments can be added at planting time. Your Bower & Branch expert Garden Center can assist you with determining the proper soil amendments.
The Desired Available Water Zone
Our goal is to stay in “the zone.” This means the soil has enough water available, but isn’t fully saturated nor is it near a permanent wilting point. Fully saturated soils do not provide tree roots with required oxygen and will result in root diseases and eventually root failure. On the other hand, soils that get too dry will lead to damaging wilting points. The secret is to hover in between these two extremes.