dogwood gone to the dogs
We purchased a dogwood tree, about 5' high, a few months ago. We planted the tree in well fertilized soil and throughout the rains it did so well. The tree grew, the leaves grew and all was good. Then the rains stopped and the heat started. We noticed, a few days ago, that the leaves had shriveled and were crisp to the touch. They actually crumbled in our hands. We were surprised since the soil wasn't dried out, but we watered the tree anyway. Today the leaves are still looking crumbled although they feel softer. A friend thought the sun was too blinding, so we purchased an inexpensive canopy to cover the top leaves. Another friend suggested we talk to it, but my husband had no kind words for it after the expense of the original purchase and the canopy. I took a branch with a few offshoots and leaves to a local nursery, but she could find no aphids or evidence of a bug infestation. We are at a loss as to how to restore it to its original glory. Any thoughts or ideas would be greatly appreciated. Thank you so much for your assistance.
Talbot County Maryland
It's possible that your dogwood was drowning. Shriveling leaves point to a root problem. That can be caused by too little water--the wilting one usually sees--but it can also be caused by too much water.
Sometimes plants are over-watered. Sometimes they drown because of a "bathtub effect". This is when the planting hole is filled with porous "good" organic soil which lets water quickly into the planting hole. Which seems good. But, if the surrounding soil is clayish, then the water can't drain out quickly because clay particles are tiny and close together. So the water sits (the bathtub) and the plants drown from sitting in water too long and the roots rot. We had torrential rains--much more than is usually applied to a plant--and that may be why the dogwood is struggling.
Yes, plants need water, but most plants won't tolerate sitting in water. They like soil about as wet as a wrung out sponge, not saturated.
The solution for the bathtub effect is to backfill the planting hole with the native clayish soil (with maybe a handful of organic amendments, but not much.)
If your tree has enough healthy roots left, it will recover slowly.
Here are some other problems, not insect or disease, that can kill a tree: http://extension.umd.edu/sites/extension.umd.edu/files/_docs/programs/hgic/HGIC_Pubs/Landscape/HG201...