I have some blackberry vines in the back yard. Last year’s crop was very small compared to the previous year. I read that the vines, after a season of fruit producing, become dormant and need to be trimmed back. I had other chores to do and did not get to the vines this year and I can’t tell which vines are the dormant ones. Is too late to prune and how can I tell which is which?
The Gardener’s Answer
Hello, Ron: Blackberries go through a dormant stage during the winter months. At this time, they are conserving energy to produce fruit the following growing season. It is not that some of the canes go dormant and stay dormant, the entire plant goes through this process and then as warmer weather arrives they break dormancy. Each plant should be pruned annually for best fruit production. If your vines were not pruned last year, I suspect this is the reason for the lack of fruit. As Kentucky gardeners, we typically grow two kinds of blackberries: semi-erect and semi-trailing. As far as pruning, this depends on what kind of blackberry you are growing. Semi-erect cultivars should be pruned for the first time during the winter dormant period. They should be cut back where the canes start to bend over. They can also be pinched back during the summer months if at any time the canes have put on more than one foot of new growth. If you are growing semi-trailing blackberries, early spring is the best time to prune them, so go ahead and get your pruners out. At this time, you will want to study each plant and pick out two or three of the most vigorous canes and remove the rest at ground level. If you know the name of the blackberries you are growing, I can give you more specific information in terms of pruning. Otherwise, for more information on growing/pruning blackberries in Kentucky, visit www.ca.uky.edu/agc/pubs/ho/ho15/ho15.pdf. This publication is provided by the Kentucky Cooperative Extension Service. Blackberries are a delicious treat and as long as they are pruned annually and given the right growing conditions, they will provide you with many years of fruit.