Blackberries and raspberries are bramble fruits that grow either erect or trailing. The blackberry is actually a hybrid of the red raspberry and includes variations such as loganberry and boysenberry. There are hundreds of variations and all are easily grown. While some variations are less cold hardy than others, all blackberries and raspberries require the same general care for healthy growth and fruit production.
Irrigate the raspberries and blackberries regularly to provide 1 to 2 inches of water each week. Water the bushes with a slow irrigation process to avoid disturbing the planting area. Adjust the irrigation levels for periods of rain and drought.
Feed the raspberries and blackberries lightly, providing one application annually. Fertilize in the late spring or midsummer using a well-balanced, slow release fertilizer such as a 10-10-10 or 20-20-20 (nitrogen-phosphorus-potassium). Do not distribute the fertilizer near the base of the plants to prevent root burn. Distribute the fertilizer in a ring around the planting area or in between planting rows approximately 12 to 18 inches from the base. Irrigate the fertilizer thoroughly into the soil.
Keep the planting area free of debris and invasive weeds. Remove weeds immediately as they appear. Pull the weeds by hand and ensure the entire root system is removed from the soil. Apply a thin layer of mulch around the roots of the raspberries and blackberries to reduce the potential for weed growth and preserve soil moisture.
Prune the raspberries and blackberries regularly to promote health. In the early spring, prune away any spent canes from the previous year's growth. Trim away any wayward growing canes that rest outside of the desired planting area. Remove any dead, dying or wilted canes, foliage and flowers.
Thin the interior canes to promote increased air circulation and light penetration. Trim the canes so that the length of each row is limited to four to five canes per foot. Remove all clippings and debris from the area to reduce the potential for disease.
Harvest the raspberries and blackberries as they become ripe. Harvest raspberries when they are easily removed from their stems. Pick blackberries for harvesting after a taste test. Look for a full, rich color and sweet taste when judging blackberries. Harvest the plants daily as berries ripen.