Leaves turning brown on Zestar apple tree - Ask Extension
The leaves have been turning brown on my Zestar! apple tree. I'm not sure if it's a disease or because the tree is lacking nutrients. The closest rese...
Knowledgebase
Leaves turning brown on Zestar apple tree #664376
Asked July 15, 2020, 9:51 AM EDT
The leaves have been turning brown on my Zestar! apple tree. I'm not sure if it's a disease or because the tree is lacking nutrients. The closest resemblance I can find online is apple scab. If it is apple scab, what is the best way to treat my tree? I have seen and read about different solutions. Thank you!
Queens County New York
Expert Response
Hello and thank you for contacting us about your apple tree. It is likely that your tree is suffering from sun scorch caused by high temperatures, dry winds, and low soil moisture. This is a common problem in July and August and affects some plants more than others.
The best treatment includes:
Deep watering - The soil across the drip zone of the tree needs 1-inch of water per week (ie. the soil should feel moist to the touch at a depth of 2-inches.) The best way to do this is with a drip irrigation system or a sprinkler set at the lowest possible setting, moving it across the drip zone.
Mulching - Use wood chips or other organic mulch, again applying it over as much of the drip zone as possible. Mulches should be between 2 and 3 inches deep, but be sure to keep it several inches away from the trunk to prevent possible rot.
Fertilize the tree regularly, but not when it is in water stress. A good all-around fertilizer will keep the tree in a vigorous condition. Be sure to follow the instructions on the label exactly. Too much fertilizer, or if applied incorrectly, can damage the tree as well as the environment.
The best treatment includes:
Deep watering - The soil across the drip zone of the tree needs 1-inch of water per week (ie. the soil should feel moist to the touch at a depth of 2-inches.) The best way to do this is with a drip irrigation system or a sprinkler set at the lowest possible setting, moving it across the drip zone.
Mulching - Use wood chips or other organic mulch, again applying it over as much of the drip zone as possible. Mulches should be between 2 and 3 inches deep, but be sure to keep it several inches away from the trunk to prevent possible rot.
Fertilize the tree regularly, but not when it is in water stress. A good all-around fertilizer will keep the tree in a vigorous condition. Be sure to follow the instructions on the label exactly. Too much fertilizer, or if applied incorrectly, can damage the tree as well as the environment.
