Leaf curl and blackened edges on grafted container apple tree - Ask Extension
Hello OSU extension,
Your team has been incredibly helpful in the past, so I am coming back with more questions! We have a 4 way grafted apple on ...
Knowledgebase
Leaf curl and blackened edges on grafted container apple tree #837621
Asked June 26, 2023, 1:52 PM EDT
Hello OSU extension,
Your team has been incredibly helpful in the past, so I am coming back with more questions! We have a 4 way grafted apple on dwarf rootstock that I picked up this past winter while still dormant, at the time the tree looked healthy, all of the grafts were clean and well healed, no visible signs of cankers or any illness. Fast forward to the last week or so I have noticed leaf curl and blackened edges on the new growth across all of the grafts. Is this fireblight or some other illness? We have positioned the tree so that it receives 6 or so hours of sunlight but is spared from the most brutal afternoon sun. I have been watering between every day to every 3 days depending on the temps, is this simply sunburn or do I need to take more drastic action? We also have a fruiting pear and a callery pear that do not appear to be suffering from this issue.
Thank you so much!
Washington County Oregon
Expert Response
In your images you are showing us apple shoots with slightly deformed leaves. In some cases the leaf tips appear stunted, in others the leaf margins are necrotic and in most cases the leaves are curled or boated upward. The affected leaves appear to be very young when the damaged happened. In one of the images the even newer leaves are coming out and look fine.
This is indicating a non-living problem (not fungus, insect, etc...). It is not from a lack of water as you are watering but it could be a root issue if you are watering too much. One or twice a week should be fine.
I do note your tree has a lot of competition from the weed free grass lawn and a strawberry (poking up from below)? It is possible that applications to the lawn are influencing the tree. Any weed and feed going out on the lawn? That might be the issue.
This is indicating a non-living problem (not fungus, insect, etc...). It is not from a lack of water as you are watering but it could be a root issue if you are watering too much. One or twice a week should be fine.
I do note your tree has a lot of competition from the weed free grass lawn and a strawberry (poking up from below)? It is possible that applications to the lawn are influencing the tree. Any weed and feed going out on the lawn? That might be the issue.
