|I had previously asked a question about big reddish brown spots on my blueberry bush leaves. it was diagnosed as rust. after more research, it seems like it may be leafspot. what fungicide should I use for these diseases & where can I get it?I have Bonide citrus, fruit and nut orchard spray (ingred. sulphur 10% and pyrethrins .25%). it says it covers this but I had previously used to no avail.
|There are lots of different fungal diseases that can attack blueberry leaves. Rust usually has orange or brown pustules associated with the spots, others may or may not develop black or brown specks (spores), but all the diseases can be somewhat controlled with fungicides such as Benlate (benomyl) or Captan. The key to control is to use fungicides as a preventative measure. Once the leaves are infected they cannot be brought back to good health, but by applying fungicides you will be protecting unaffected leaves and also stopping the spores from splashing or blowing onto the other leaves. Timing is really important when using fungicides. Don't wait until you see the signs; spray instead when the new leaves are unfurling. You may want to prune your blueberries back and then use a fungicide every 7-10 days until the leaves are fully mature. Good luck with your blueberries.