Plant Problem Diagnostic
Why Is My Tree Dropping Leaves in Summer?
The short answer
A tree dropping leaves in the middle of summer is most commonly reacting to drought or heat stress — when water is scarce, a tree may shed older, less-productive leaves to reduce the load it has to support. Watch for lighter or yellow-green foliage, browning leaf margins (leaf scorch), and wilting alongside the drop.
That said, summer leaf drop could also be caused by root damage, a soil or planting problem, disease, or borers, so it is worth ruling out the obvious first: check whether the tree has been watered deeply during dry spells and whether it was planted recently. If the tree keeps declining, is dropping green leaves heavily, or shows dieback, have a certified arborist or your local Extension office diagnose it in person.
The most likely cause: drought and heat stress
During hot, dry stretches a tree can struggle to move enough moisture to every leaf, so it drops some to conserve water. Younger and recently planted trees are more vulnerable because of shallow, still-establishing root systems.
Signs that point to drought stress include leaf scorch (brown, crispy margins), off-color foliage, wilting, and early fall color. Deep, slow watering during dry periods is the first thing to try.
What else to rule out
Summer leaf drop is not always drought. Root injury, compacted or poorly drained soil, transplant stress, foliar disease, and borer or canker problems can all cause it, and a drought-stressed tree is more prone to borers and cankers on top of it.
Check whether buds are still forming at the base of dropping leaves — normal bud development is a hopeful sign. If you cannot identify the cause, or the decline continues, escalate to a certified arborist or your Extension office rather than guessing at a treatment.
Sources
Reviewed 2026-07-18. We cite university Extension, government, and established horticultural sources — and never invent pesticide rates or dangerous treatments.
- South Dakota State University Extension — Trees & Drought Stress — Drought-stressed trees show lighter/yellow-green foliage, leaf scorch, wilting, and premature leaf drop; young/recently planted trees most at risk.
- Alabama Cooperative Extension System — Drought and Landscape Trees — Trees drop leaves under drought to reduce water demand; deep watering recommended; drought stress increases vulnerability to borers and cankers.