Q: My blueberry bush is not doing well. I have enclosed photos, what could be wrong?
A: Your blueberry bush probably has Blueberry stem blight, which is caused by Botryospheria dothidi. This disease has caused significant plant mortality of some southern highbush cultivars in Florida. The causal fungi are usually present in orchards and blueberry fields and cause a number of different diseases on various host plants. Rabbiteyes are usually not seriously affected by this disease but some southern highbush cultivars are extremely susceptible. ‘Misty’ appears to be more susceptible to infection and death by blueberry stem blight than most other southern highbush cultivars. ‘Misty’ tends to produce very heavy crops, even as young plants. Over-fruiting predisposes blueberry plants to stem blight. There is no chemical control for blueberry stem blight. Pruning out infected wood and removing flower buds and fruit from young plants, pruning mature bushes to thin crop loads, and minimizing drought and other plant stresses appear to be the best methods of control. If the plant does not survive you might consider replacing it with a hardier rabbit-eye variety better suited for this area. Attached is a publication from the University of Florida/IFAS called “Blueberry Gardener’s Guide.” http://edis.ifas.ufl.edu/mg359