Blackberries (Rubus spp.) are included in the group of small fruits generally referred to as 'brambles' or 'caneberries.' They have perennial crowns and roots. Most blackberry types produce canes the first season (primocanes) that do not bear fruit. The following year these are called floricanes, and bear fruit and then die naturally after harvest. Primocane-fruiting blackberries are an exception. They produce fruit on the primocanes in late summer and fall and again on these same canes (floricanes) the following July and early August before dying. With favorable growing conditions, brambles may produce for 12 or more years. Blackberries are grouped according to their growth habit: erect, semi-erect or trailing. Erect (thorny and thornless) and semi-erect (thornless) blackberries grow and yield well in most parts of the state. The trailing types are not recommended for commercial production in Kentucky due to their lack of winter hardiness. Primocane-fruiting thorny and thornless blackberries also do well in Kentucky; however, hot summers substantially reduce the primocane crop because a week of temperatures above 85 degrees F causes flowers to abort.