The spring pruning procedures for the different types of raspberries are outlined below. Summer-Bearing Red Raspberries Remove all weak, diseased, and damaged canes at ground level. After thinning, remaining canes should be spaced about 6 inches apart. Also, prune out the tips of the canes which have died due to winter injury. Cut back to live tissue.
Red raspberries sucker profusely.
This procedure allows you to obtain both a summer and fall crop. While the summer crop is lost, the fall crop should mature one to two weeks earlier. Black and Purple Raspberries Remove the small, weak canes, leaving only four or five of the largest, most vigorous canes per clump or plant. Cut back the lateral branches to 12 inches in length for black raspberries and 18 inches for purple raspberries. The pruned material should be removed from the garden area and destroyed.