This Forum will close on Wednesday 27 March, 2024. Please refer to the announcement on the Discussions page for further detail.
black spots on leaf
Crypto
Posts: 3
My rose of sharon which was planted this spring started to have black spots on the leaves. We did have a lot of rain. Could this cause the problem. I live in zone 5. what do i do to stop the black spots without chemicals.
0
Posts
It's more than likely Black Spot, Crypto, a very very common fungal disease with roses. Spraying of any kind has to be preventive - ie, before the symptoms appear. Once the plant is infected your options are limited to removing the infected leaves and destroying them.
Apart from preventive spraying, the best way of guarding against infection is housekeeping. Keep healthy leaves dry; make sure there's plenty of sun and air circulation; be very careful not to transfer the disease from infected leaves to healthy ones via your hands or secateurs, etc; and keep the ground around the plant clear of fallen leaves and other plant debris. The fungal spores can and will live on in the detritus on the ground around the plant.
What 'rose of sharon' are you talking about Crypto. It's a common name for several different genus of plant. As far as I know it's never been a named rose, and the advice you'll get will have to be plant specific. a picture would help.
I believe Dave Morgan, my rose of sharon is the blue chiffon variety. These are some pictures and i included a picture of the label i got when i bought the plant.
This particular leaf in the photo is located at the bottom of the plant. There were many other leaves that I plucked out. I must have removed twenty or more leaves with black markings on them. I will pay attention to see if it's a bird problem, but i don't think it is. The other plants don't have this mark.
If it's not black spots, what do you think it might be?
Well it's Hibiscus, and it looks pretty healthy other than the spotted leaves you mention.