Fall Blackberry Pruning! Blackberry plants grow fruit as well as new canes during the growing season. The new canes are what continue to grow and produce fruit the following year. After a cane has produced it will most likely die back to allow the newer canes to grow, and you can help out this process by pruning. Pruning back the old canes down to the ground will help to further establish the plant and focus the energy to the new, first year, canes. Follow us to see how we prune our blackberries