How to Troubleshoot Raising Black Raspberries

Purchase the black raspberries at a nursery if there are problems with viruses and the plants were either transplanted or wild in nature. Many nurseries sell plants that are certified virus free, which will help greatly in reducing the spread of potentially harmful or deadly viruses.

Provide wind protection or plant the raspberries on a high, sloping site if the raspberries are not surviving well in cold temperatures. This is often caused by wind as much as the cold, and the plants require protection and shelter from the wind for the best results.

Water and fertilize the soil if the plants have low production. Keep other plants at least 300 feet away from the black raspberry crop to reduce the transfer of diseases, and do not plant raspberries in areas where a bramble crop such as tomatoes or eggplants has been previously located.

Weed the area frequently if the raspberries are low producing, and cover the ground with black plastic mulch. Placing the plastic mulch in fall or early spring will help reduce the weeds and can be removed after approximately two months to tend to the soil.

Apply fertilizer with equal parts nitrogen, phosphorus and potash if the raspberries are not thriving. Use approximately 1 lb. of fertilizer for every 35 feet of linear row.

Cut the top 2 inches off the raspberry canes in early summer to encourage branching if there is no new growth or fruit formation. Cut the side branches to 6 inches and reduce to three or four canes.