Blackberries are thriving, bushy plants that expand quickly with the right care. Thornless blackberries are specific varieties that grow without the standard blackberry's long, sharp thorns, and are hardy down to Zone 5, which drops to winter temperatures of -20 degrees Fahrenheit. All blackberries are successful in Florida, with some soil and water modifications.
Types of Blackberries
Thornless blackberries grow in erect and trailing varieties. Erect blackberries grow strong canes that support themselves, while training types grow long climbing vines.
Florida Growing Zones
Southern Florida remains very temperate all year, and can support any type of blackberry. Erect blackberries, like Cherokee and Cheyenne, are hardier than some of the trailing types, and may grow better in northern Florida, where winter temperatures drop lower than 20 degrees Fahrenheit.
All blackberries require full sun and good drainage. Do not plant them in swampy areas of Florida, since their roots will rot in standing water. Do plant them in a spot that has plenty of room for their growth, which may reach 7 to 12 feet in height and width.
Blackberries require rich, quick-draining soil to keep their roots from rotting. Regardless of what kind of blackberry you're planting, mix quick-draining soil and compost into the native soil to keep it loose and fertile for blackberries.
Water thornless blackberries with 1 to 2 inches of water a week to supplement natural rainfall in Florida. Restrict watering in winter, when the bushes go dormant.
Erect blackberries grow tall, strong canes and do not require any additional support, while trailing blackberries always require some sort of trellis system to hold them up and maintain air circulation. In the heat and humidity of Florida, it's very important to stake your blackberries up, to protect them from swampy soil and maintain good air movement.