pruning high bush blueberries
My 15 year old high bush (6-8ft H x 3' W) blueberries usually give a good yield. This year there are few berries. The plants look healthy, and have been fertilized and mulched each year. Although I do prune a little each year they do need more pruning. If I wait to prune them until winter I will probably not have any blueberries next year. What happens if I prune them now? if I can prune, can I do a hard pruning now and take out most old stems as well as decrease the overall height to 4-5ft.
Montgomery County Maryland
Hi- blueberry plants stay productive through renewal pruning- removing old canes (8 years of age) with exfoliating bark right above the crown. This will promote new shoot growth from the crown. Mature plants should have 1-2 canes from 1 year to 8 years age.
It would be fine to prune now, especially if some of the oldest canes are relatively un-productive. You can also reduce the overall height to make them more manageable. You may lose a little fruit but it will re-invigorate your plants. Keep them well-watered during dry periods and fertilize now with ammonium sulfate fertilizer (21-0-0).
HGIC web pages on blueberry: https://extension.umd.edu/hgic/topics/blueberries