Extension

One of the biggest investments homeowners make in their landscape is in trees. Therefore, proper irrigation is essential to maintain tree health – especially when establishing newly planted trees.

The most efficient way to irrigate new landscape trees is with a drip or automated irrigation system. However, this isn’t always possible. The simplest way is to set the hose end next to the tree and allow a slow trickle to run long enough to moisten the root ball. This is called the open hose method, and it works well for the most part. However, hoses are often forgotten, and the tree gets overwatered. This also leads to water waste through run-off. One way to alleviate the problem is to install timers on the spigot that will turn off the water after a set time.

Another option is circling a soaker hose around a tree to distribute water more evenly over the root zone. Soaker hoses are affordable and readily available. The downside is that it is difficult to determine how much water is being applied. Soaker hoses don’t typically distribute water evenly along their length. Fortunately, with applications like this, it’s not a major concern.

Homeowners can use drip irrigation without installing a complete drip system; however, complete systems can be purchased at most garden centers. For DIYers, a simple, inexpensive alternative is using milk jugs or 5-gallon buckets. Drill holes no larger than ¼-inch in the bottoms of the containers to allow the water to slowly trickle into the soaking area. Newly planted trees with trunks about 2 inches in diameter require 2-3 gallons of water every four to five days. Refill the buckets every couple of days to keep the soil moist around the root ball.

Another alternative is to purchase plastic pouches filled with water and then secure them around the tree. The bags have holes at the bottom that allow water to slowly seep into the soil.

Larger, established trees are generally more drought-tolerant. But drought conditions like Oklahoma has experienced over the past few years will require supplemental irrigation. Established trees have massive root systems, often four to five times the width of the tree canopy. Placing a water hose at the base of a mature tree is not usually effective. Irrigation should cover the entire root zone, including the area under the tree's canopy and, if possible, beyond. Water to a depth of 1-2 feet to ensure water reaches the roots. Basic lawn irrigation isn’t enough for big trees. Soaker hoses can be handy for slowly irrigating the large root area.

Remember, trees are a significant investment in the landscape and are certainly worth the time, money and effort necessary to ensure their continued health.