Black raspberries are pruned very differently than red raspberries. Black raspberries grow on canes that grew the previous year. Because of this, you will want to train and prune your new raspberry canes for optimal production the following year. Pruning your black raspberry bush is not difficult. By pruning the bush or bushes three times over the year, you will ensure optimal plant health and growth.
Prune your black raspberries three times a year. Pruning three times a year will ensure optimum fruit production and plant health.
Cut the lateral branches back to eight to ten inches in the spring. This will encourage good new growth and minimize energy and nutrient use by non-fruit-producing branches. Prune the canes back with a pair of pruning shears.
Tip new canes by removing the top two to three inches of new growth in mid-summer. If you are growing your black raspberries without supports, tip them when they reach 24 inches high. Tip the raspberries with a pair of pruning shears.
Prune out the canes that have produced fruit right after harvest by clipping them off near the ground with a pair of pruning shears. Black raspberries produce fruit on the previous year's growth. Your summer pruning and preparation affected the canes that will carry next year's raspberry crop.