Blackberries are an excellent addition to a southeastern garden: they are easy to grow, produce abundant fruits that are delicious, highly nutritious and very healthy (blackberries are among the fruits with a highest antioxidant content). On top of this, they are versatile and can be consumed fresh or used to prepare jellies and classic southern desserts such as blackberry cobbler and pies. Also, currently there are many thornless varieties available that fit very well with the demands of backyard gardeners.
How do you know if blackberries are well suited for your backyard garden? As long as they are planted in full sun, and have a well-drained and fertile soil with a pH between 5.5 and 6.5, they will thrive. They should be planted between 3 and 4 feet apart, and all varieties benefit from a trellis or a fence that helps to keep the canes off the ground.
Blackberries are perennial shrubs that produce shoots (canes) that live for two years. During the first year of growth, canes are called primocanes (they are typically vegetative); these canes will flower and produce fruit the second year, then they are called floricanes. Floricanes produce fruit for one year and die after fruiting, thus, blackberries always need to be pruned after harvest. Nowadays, there are also primocane-fruiting varieties available: these varieties produce two crops a year as they bear fruit in both primocanes (late summer) and floricanes (late spring, for our conditions in SC). However, a variety trial carried out at Clemson University Musser Fruit Research Farm showed that their yield was considerably poorer than other varieties after the second year. Varieties producing the highest yields under our conditions were Natchez, Navaho, Von, and Osage, followed by other such as Triple Crown, Ouachita and Arapaho. Navaho and Ouachita had some of the highest brix (sugar content) and Prime-Ark® Freedom, a primocane-fruiting variety, had bigger fruit size.
For more information, see HGIC 1400, Blackberries.