As summer 2021 has progressed, we are well behind on rainfall since May here in Salina and other parts of central Kansas. This is a good time to be reminded about the importance of prioritizing what and how we water during the summer.
Most folks don’t have time to see to it that everything in their yard is taken care of perfectly and for most plants that really isn’t a big deal. Even most trees are tough, but when one is in danger of being lost it is a much bigger problem than losing a small shrub or even a lawn.
Trees are not replaceable. A 10-year-old shrub can be replaced to full size in a matter of only a couple years, but a 30-year-old tree will take 30 years to replace. With this in mind, take a little extra time to care for the important trees in your landscape this summer, fall and winter.
Make tree care the priority in times of environmental stress. Proper watering is the very best way to keep any tree healthy and strong. With May 2021 being fairly wet, it may seem like old established trees should still be fine, but deep watering is often needed sooner than expected after a period with wet soils. This is due to the fact that the previously wet or waterlogged soils were deficient in oxygen which actually slows down root growth significantly. The reduced spring root growth means trees and plants come under summer stress much more quickly than expected.
Most tree roots are found in the top 15-18 inches of the soil and any watering should attempt to get moisture down to at least 12 inches. Deep and infrequent watering is best since the soil needs to dry between watering to allow the much needed oxygen to re-enter the soil.
What to do
Newly transplanted trees need at least 10-15 gallons of water per week, and on sandy soils they will need that much applied twice a week. The secret is getting that water to soak deeply into the soil, so it evaporates more slowly and is available to the tree’s roots longer.
One way to do this is to punch a small hole in the side of a 5-gallon bucket and fill it with water. Let the water dribble out slowly next to the young tree. Refill the bucket once or twice more and move to another side of the tree and you have applied the needed water. Tree watering bags which easily attach around the tree are another great way to slowly and properly water a young tree.
For larger trees check the soil moisture to see if water is needed by probing the soil. If the soil is hard and difficult to push a screwdriver through, water is likely needed. A perforated soaker hose or just laying a garden hose out on a slow trickle are possible ways to water. Drip irrigation is becoming much more common and easy to use as well and offers a very efficient means of watering specific plants. The key is to water slowly to avoid water running off and being wasted.
Regardless of the watering method used, soil from should be wet 12 inches deep after you have watered. The target area to water on a large tree is the area starting ½ the distance between the trunk and the dripline out to the edge of the tree dripline (tips of branches). Use a screwdriver or something similar to check the depth the water has reached after watering. Dry soil is much harder to push through than wet.