I am interested in cultivating my wild black raspberries so I will have an easier-to-pick patch. Also, what is the best time of year to transplant them?
If you are simply cleaning up a wild patch, cut out the old, dark brown canes (stems) at the ground, and then throw some compost over the bases of the newer canes, which are usually green or reddish brown. If the new canes are so big and unruly that they bite you when you get near the patch, use pruning loppers to top them back to about 8 feet. They will then grow short lateral stems, which often bear a good crop of berries.
Anytime from early spring to early summer is good to dig and move black raspberries (Rubus occidentalis) and other wild brambles. Like other wild ones, black raspberries can carry viral diseases, so it’s best to plant them as far as you can from cultivated red raspberries. Or, start with certified disease-free plants of a tasty, improved variety such as ‘Jewel.’ Black raspberries grow best in fertile, well drained soil.
Whether wild or cultivated, black raspberries that are moved to a new spot will spend their first season growing new canes, which will bear the following summer. Cane production will be much stronger once the patch is established. Two years from now, you should be buried in black raspberries.
— Barbara Pleasant, contributing editor