Summer is berry time. Yes, grocery stores now carry a wide variety of berries nearly year round, but berries grown to perfect ripeness that only have to travel from back garden to kitchen (if they make it that far) are so superior. Red raspberries, blackberries, and their relatives ‘Boysen,’ ‘Logan,’ ‘Olallie,’ and ‘Marion’ berries are among the quintessential flavors of summer. All are relatively easy to grow, but they do require some attention beyond picking the delicious harvest.
In August sometime, the berries will slow and then stop. This is the time to prune and tie them up so next year’s growth and harvest are maximized. It’s one thing to brave the stickers and thorns when harvesting such luscious fruit, but wading in to do the necessary pruning and tying can be a real ordeal. However, periodic maintenance will ensure continued vigor and fruit production, and, frankly, the neat rows of canes will soon turn to a bramble if not thinned appropriately.
Gear up for this chore by putting on long pants and a long-sleeve work shirt. Wear sturdy gloves and a cap or scarf, but be prepared for a few pricks and scratches anyway. The goal is to cut clear to the ground all the canes that had fruit this year. Then tie up the new canes (those that grew up this spring and summer) that will bear fruit next year. When all the old wood is out of the way, assess the spacing of the new canes and do any thinning necessary. Leave only the 12 to 16 sturdiest shoots from each original plant for blackberries. Raspberries may be suckering farther away from the original crown and should be thinned to six to eight inches apart. There may also be canes springing up in between the rows that should be removed. Both blackberries and raspberries do best with a sturdy trellis on which to tie the canes. Spread the canes fanwise along the horizontal bars of the trellis after topping them at six to eight feet. Use a natural fiber-like manila twine or sturdy cotton string. These will be a little easier to remove next year than some of the stretchy (and way too gaudy) plastic tapes. Side shoots will grow from these main canes to produce next year’s fruit. Another pruning will be necessary in late winter or early spring to shorten the late-summer side branches. Cut them to one foot in length, and their fresh spring growth will produce berries for the coming summer.
Blackberries can be susceptible to scale, borers, leaf spot, and powdery mildew. There are resistant varieties, and starting with healthy plants is a must. In cold winter locations, fertilize just before new growth starts. In milder areas, split the fertilizer up, and apply two or three times throughout the growing season. To prolong the harvest, plant several varieties. There are early-, mid-, and late-season types to provide a succession of pickings over the summer.
Raspberries also have some diseases like anthracnose and pests such as spider mites and cane borers. If borers are detected, cut canes to the ground below the tiny entry holes, and dispose of them offsite. On paper, this might seem daunting, but keep the delicious harvests firmly in mind, and the few pricks and scratches will seem worth the effort.