Oakleaf Hydrangea Leaf Spot
My new alice oakleaf came with some minor leaf spot at the bottom of the shrub. The spots are irregular in shape and purple/red in hue. With 2 weeks of rain at least once a day the spots are spreading quickly up the poor baby hydrangea! From what I've read, it doesn't sound like the plant will be killed by the outbreak, but it isn't very attractive. Has anyone found an effective treatment they could recommend? With all this rain, will anything really help anyway?
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luis_pr
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- Location: Hurst, TX USA Zone 7b/8a
Humid weather fuels the growth of fungi. Short of applying a leaf spot fungicide, cutting off the infected leaves or putting an umbrella over Alice, there is little one can do.
A fungicide that attacks leaf spot or the anthracnose fungus should help: Cleary's 3336, Daconil Weather Stix, etc. Because you are getting a lot of rain and often, I would try some fungicides. Kind of debetable if you want to wait until the rains stop though. But over here where it is not raining, I would wait and let the summer temperatures make life dry and hot for the fungi. It is cheaper.
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Keep the area underneath the plant free of plant debris. Make sure there is separation between this shrub and others so the air currents will help and keep the leaves dry. Do not keep the soil wet/humid for long periods of time. Do not water the leaves; instead, water the soil early in the mornings (5-7am). The infected leaves and ALL blooms should be thrown in the trash when the plant goes dormant.
A fungicide that attacks leaf spot or the anthracnose fungus should help: Cleary's 3336, Daconil Weather Stix, etc. Because you are getting a lot of rain and often, I would try some fungicides. Kind of debetable if you want to wait until the rains stop though. But over here where it is not raining, I would wait and let the summer temperatures make life dry and hot for the fungi. It is cheaper.
)Keep the area underneath the plant free of plant debris. Make sure there is separation between this shrub and others so the air currents will help and keep the leaves dry. Do not keep the soil wet/humid for long periods of time. Do not water the leaves; instead, water the soil early in the mornings (5-7am). The infected leaves and ALL blooms should be thrown in the trash when the plant goes dormant.
Thank you for the helpful information! It's another rainy day here, but it looks like the rain might take a break next week so hopefully poor Alice will dry out a bit!
You mentioned discarding fallen leaves when the plant goes dormant, which I will definitely do. Would this help eliminate the problem next year? Does the fungi survive the winter and increase the chance of a problem again next year? Fortunately since she is so little now, she has plenty of room around her as she will grow big one day so she has some good air circulation and won't be infecting her neighbors... hopefully!
You mentioned discarding fallen leaves when the plant goes dormant, which I will definitely do. Would this help eliminate the problem next year? Does the fungi survive the winter and increase the chance of a problem again next year? Fortunately since she is so little now, she has plenty of room around her as she will grow big one day so she has some good air circulation and won't be infecting her neighbors... hopefully!
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luis_pr
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- Posts: 824
- Joined: Sun Jul 05, 2009 8:31 am
- Location: Hurst, TX USA Zone 7b/8a
It should help since the fungi can be found in the leaves, in the stems and in the mulch. That is why some fungicides say to spray under the leaves and throughout the branches of whatever plant one is spraying.
If you were to put the leaves in the compost pile, the fungi would spread so it is best to just dump them in the trash. When I have had similar problems, I opted to prune leaves that were heavily infected and left the ones with small affected areas. Then I cut them off in December (when my hydrangeas usually go dormant).
If you were to put the leaves in the compost pile, the fungi would spread so it is best to just dump them in the trash. When I have had similar problems, I opted to prune leaves that were heavily infected and left the ones with small affected areas. Then I cut them off in December (when my hydrangeas usually go dormant).
Lord, oh Lord. 