What is happening to my jasmine? - Ask Extension
My jasmine has some kind of blight that seems to be killing it. It dropped lots of leaves during the summer, looking like it was dying from the inside...
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What is happening to my jasmine? #779563
Asked December 29, 2021, 8:26 PM EST
My jasmine has some kind of blight that seems to be killing it. It dropped lots of leaves during the summer, looking like it was dying from the inside out. The remaining leaves are dark red. Whatever the problem is, it is spreading. Newly infected areas have distinct red spots on tops and undersides of leaves. Is this rust or something worse? Is there a way to save the plant?
Clackamas County Oregon
Expert Response
Willi,
Thank you for the images of your jasmine.
Star jasmine is marginally hardy here in the Pacific Northwest. The red spots and blotches are a response to low temperatures.
A more severe indication of excessively low temperatures would be dropped leaves.
If low temperatures threaten again this winter, consider temporary protection during the coldest hours. You can use s commercially packaged frost blanket, a non-woven fabric you can obtain at a garden center. Or, in an emergency, throw a bed sheet over the trellised plant.
Caution: Be certain to remove the protection during daylight hours when temperatures rise.
Sorry for the delay in sending a response. Computer gremlins temporarily fouled up the works.
Thank you for the response below, sent earlier this year. I have new information that leads me to think cold weather is not the problem. The jasmine in question put out new growth this spring and I hoped it might be bouncing back. Unfortunately, the new growth has now wilted and died, shown in this photo:
The jasmine right next to it is still thriving... so far. The contrast between these two adjacent plants is dramatic, as this photo shows:
However, on the other side of the dying jasmine, I have a lilac and a quince that are both showing signs of distress. They are still mostly healthy so far, but the lilac has some leaves with large dark blotches, and some that seem to be shriveling from the outside edges inward (next two photos):
The quince has some leaves that look almost like the black spot my roses get, but then it progresses to entire twigs drooping and turning crispy brown, while the rest of the branch is still green:
I suspect all of these plants have some kind of fungus but I don’t know what kind or how to treat it. Any pointers would be very welcome.
Many thanks!
Willi
Hi Willi- Sorry for taking so long to get back to you. Your question has been bouncing around our site for a bit!
Your pictures and diagnosis agree with what I was seeing on your Jasmine, which is Leaf Spot, a fungus encouraged by our crazy weather of the last two years. The Washington State Extension offers this advice for controlling leaf spot:
Your lilac and quince look to be very densely planted and may not be getting enough air circulation for our wet spring weather this year. I can also see an insect and insect "skin" on your quince picture so there may be some damage from whatever critter is inhabiting your dense bushes.
At this time of year, with our heat and August dryness coming, I would not do anything except remove and trash (not compost) the dead leaves and branches. Then next spring, after bloom, do some pruning as listed in the attached article.
https://extension.oregonstate.edu/news/prune-lilacs-soon-after-bloom
Oregon state horticulturist Neil Bell says winter pruning of the quince is acceptable ... "if the goal is to remove some older canes, to even out the canopy, or thin out the center to facilitate air circulation" which might be the case of your quince.
It's good that you are keeping an eye on the plants and I'm so sorry about your lost Jasmine. Good luck with the healthy one,
Your pictures and diagnosis agree with what I was seeing on your Jasmine, which is Leaf Spot, a fungus encouraged by our crazy weather of the last two years. The Washington State Extension offers this advice for controlling leaf spot:
- Remove and destroy affected plant parts
- Protect unaffected plant tissue with appropriate fungicide applications. Application timing is critical. Read and follow label instructions and make sure your plant is listed.
- Avoid wetting leaves if the leaf spot or blight is caused by a fungus or bacteria.
- Increase plant spacing to improve air circulation and speed drying of foliage.
Your lilac and quince look to be very densely planted and may not be getting enough air circulation for our wet spring weather this year. I can also see an insect and insect "skin" on your quince picture so there may be some damage from whatever critter is inhabiting your dense bushes.
At this time of year, with our heat and August dryness coming, I would not do anything except remove and trash (not compost) the dead leaves and branches. Then next spring, after bloom, do some pruning as listed in the attached article.
https://extension.oregonstate.edu/news/prune-lilacs-soon-after-bloom
Oregon state horticulturist Neil Bell says winter pruning of the quince is acceptable ... "if the goal is to remove some older canes, to even out the canopy, or thin out the center to facilitate air circulation" which might be the case of your quince.
It's good that you are keeping an eye on the plants and I'm so sorry about your lost Jasmine. Good luck with the healthy one,
This is very helpful info. Thank you so much! I’m working on removing and disposing of dead and diseased growth and will do some thinning in the fall. I’ll look for an appropriate fungicide.
You are very welcome... and let us know if you have further problems.
