The first variety of blackberry is the erect type which has arched, self-supporting canes. The second variety of blackberry, the trailing type, has canes which are not self-supporting and must be tied on a trellis. Boysenberry and Youngberry. There are several varieties of thornless blackberries, but they're usually of the trailing type and are commonly less productive than the thorny varieties. Planting methods You can plant blackberries by using either root cuttings or transplants.
Root cuttings are more economical.
However, transplants produce berries about a year earlier than root cuttings. You should plant blackberries on four-foot squares or in a hedge fashion on rows spaced six feet apart. A well prepared plant bed is essential for blackberries. Deep cultivation and turning under one or two cover crops prior to planting improves the physical condition of the soil . The deeper planting should be in sandy soils while the more shallow planting should be in heavier soils.