Browning leaves can mean a tree is getting too much or too little water. It can be difficult to figure out what’s causing the problem, but here are a few simple tools to help you decide if your trees are being overwatered or underwatered.
First, look at your tree carefully and apply this rule: If the tree is browning on the east, north, bottom, or interior, then you have an overwatering problem. If the tree is browning on the west, south, top, or exterior, you’re not giving the plant enough water.
Second, look to see if there is a pattern to the brown. It’s not always a clear, discernible pattern, so look carefully.
If the tree is underwatered, there will not be enough water in the leaves to replace the moisture lost through evaporation. The leaves most prone to desiccation are those that receive the most heat (west, south, top, and exterior). The leaves get scorched and dry up. Conversely, if the tree is overwatered, too much moisture saturates the leaves, and they cannot function properly. The leaves (east, north, bottom and interior) will not only turn brown but will be limp and flexible. After enough time, the dead leaves dry up and become brittle.
For a tool to confirm your suspicions, try a soil moisture probe, available at garden centers for about $10. Insert the probe into the soil around the base of the tree and the meter will tell you whether the soil is wet or dry.
If you do not have a probe, a long screwdriver also can be used. After insertion in the soil, if the screwdriver comes out clean and dry, the soil is too dry. If mud or moisture remains on the tool, the soil is too wet. The screwdriver should have some moist dirt on it.
You can also use your finger to test moisture levels.
One single measurement can be misleading, so test the moisture several times over one or two weeks in several locations around the tree.
After making any changes to your watering schedule, you should continue to check the soil moisture to be sure the tree is getting the proper amount of water.
Robert Brudenell is a certified master arborist and owner of The Natural Way Inc. Send questions to robert@thenaturalwayinc.net
