Sourwood – A Hearty and Thirsty Tree
Q: I planted a sourwood tree last fall, perhaps five feet tall. It leafed out this spring and then the leaves started wilting and turning brown around the edges. It didn’t all happen at once; first a little branch, then another, but now lots more. It started on the street side. I wonder if a neighbor sprayed something on it. Also, I fertilized with a general shrub/tree slow release granular fertilizer. Other than water regularly I haven’t done anything. Do you think I can save it?
A: You’ve heard of Robert’s Rules of Order haven’t you? I am going to propose Walter’s Rule of Tree Care. My rule is that the trunk thickness of a newly-planted tree determines how long you must baby it.
How thick is the trunk of your sourwood, measured a foot from the ground? The thickness, in inches, denotes how many years it will take before the tree becomes well established. The brown edges of the leaves tell me that they are not getting enough water. That would be a common problem for trees which have been planted in the past twelve months. It still has few roots and needs a weekly deep watering until next fall.
The fertilizer you applied probably worsened the problem. It forced many new leaves to grow on the tree. That growth demanded even more water, putting more stress on the roots. Even so, sourwood is a tough tree. If you water it conscientiously, once each week, it should pull through.