The leaves on the raspberry bushes started turning yellow last September, then turned brown and fell off. The canes turned brown and the berries shrivelled up. It has started again this year and is spreading. I would like to know if there is any spray I can use to stop it. I started these bushes three years ago and purchase disease resistant bushes.
Red Raspberry Problem
Certified GKH Gardening Expert
Unfortunately, it sounds like your raspberry plants are suffering from Verticillium wilt fungus, which also commonly affect blackberries, tomatoes, and potatoes. There is little you can do now other than pull the plants and fumigate or sterilize the soil before replanting again.