Botrytis Blight is a rose fungus also called Gray Mold, that causes the buds to turn black. These buds may not open. If they do manage to open, the flowers might be flecked with yellow or brown and covered with a gray fuzzy growth. Botrytis Blight causes the leaves, stems and growing tips to also be affected, and also turn black.
Has this rose fungus infection ever happened to your roses? Ever scratched your head and wondered what it was?
Plant diseases fungus such as this is a moderately serious rose fungus.
Roses fungus such as this gray mold,are generally noticed, and become a problem when the weather is cool and damp.
The best rose fungus treatment for this fungus on roses is to prevent it! How can you prevent it?
Note: Be sure to dip your pruning snips in some bleach water to disinfect them, so you won't spread the fungi plant diseases to other plants. I keep a bottle of bleach in the potting shed, along with a plastic pail. When I head over to the roses, I have it ready. It seems there are always flowers to snip off (deadhead). So why not be prepared?
By inspecting the bushes as often as you can, you can get an early jump on little problems such as rose bush fungus before they turn into big ones!
One of my readers has reported dusting the leaves with coarse ground corn meal with good results. From the feed store not the grocery store)
The corn meal makes the surface of the leaves very acidic. (To acidic for the likes of fungus).
Liberally sprinkle the corn meal on the leaves and some on the ground under/around the bush.
My notes: I tried this with a bush that had Black spot last year, with great results!
For More Rose Problems you may encounter: