Guide to Growing Blackberries

Blackberries can be picked from hedgerows, but garden varieties generally have bigger, tastier fruit. You can also choose from several hybrid forms, which are just as easy to grow but offer something slightly different.

How to Grow

Blackberries and their hybrids, like loganberries, are vigorous climbing plants and prefer a sheltered site. Blackberries will tolerate light shade and poorer soil, while the hybrids need full sun and richer growing conditions. Bare root canes should be planted in winter, when all stems should be cut back to healthy buds 8 inches (20 cm) above the soil. Container-grown plants can be planted all year round if kept well watered. Enrich the soil prior to planting by digging in well-rotted organic matter. Feed annually with rose fertilizer, or apply more organic matter in the spring, and water plants well, especially when in fruit.

Harvest regularly since blackberries and the hybrids ripen over several weeks, and it will take several sessions to pick the whole crop.

Varieties to Try

Some blackberry varieties are thornless (TL), making them easier to harvest. Try ‘Fantasia’, ‘Helen’ (TL), ’Loch Ness’ (TL), ‘Oregon Thornless’ (TL) and ‘Silvan’ varieties.

Pruning and Training

Blackberries and the hybrids are grown against wires and can be trained in several ways. Fruit is produced on canes formed the previous summer, so the aim is to separate these canes from new growth that will fruit next year. Wear gloves because blackberries can be very thorny. Consider these various pruning and training methods: 

• The upright fan method of training blackberries and hybrids involves cutting all fruited canes to the ground in the fall, and tying in the current year’s growth on either side to form a fan. The one-year-old, fan-trained stems will fruit the following year with new stems trained up the center until fall. The whole process is then repeated each year. 
• The trailing fan method differs from the upright fan method. Here, fruited stems are also removed in the fall, and one-year-old growth is tied in to form a fan. The difference is that the new growth is trained across the ground, then trained up to the wires in the fall to replace the fruited growth. This method suits bigger gardens with ground to spare. 
• The alternate bay method involves training the new season’s growth on the opposite side to where the fruiting stems, produced last year are trained. In effect the fruiting side of the plant alternates left or right from one year to the next. Fruited stems are removed in the fall. This method is a good choice for smaller gardens. 

Watch Out for These Pests and Diseases

Blackberry cane spot causes gray or purple spotting on the canes, which die back. Infected canes should be destroyed immediately. Raspberry beetle may also affect crops. 

Raspberry spur blight can also be a problem for blackberries, causing purple-gray areas around buds on the canes. The following year, canes produce weak growth and may wither and die. Cut out and destroy infected canes.