Blackberry plants are perennials, meaning the root system survives and returns year after year to produce new growth. This long-term persistence comes from the underground crown, which can live for many years, sometimes even decades. However, the individual stems, called canes, follow a biennial life cycle, lasting only two years until they die back after fruiting. Understanding this two-part system—a perennial root with biennial canes—is the foundation for managing blackberries.
The Perennial Nature of Blackberry Plants
The root system and crown grant the blackberry plant its perennial status, consistently sending up new canes each spring. Canes are classified based on their age, which determines their function. First-year canes, known as primocanes, emerge from the crown and focus on vegetative growth throughout their first season.
Primocanes are thick, green, and fleshy, growing taller and developing lateral branches but not producing fruit for most varieties. These canes store energy over the winter, hardening off and becoming woody. They enter a dormant phase to prepare for the following year instead of dying back after the first season.
In their second year, these overwintered primocanes transition into floricanes, the reproductive structures of the plant. Floricanes develop fruiting laterals, or side branches, that produce flowers and eventually the summer blackberry crop. Once the floricane has finished its fruiting cycle, usually in late summer, it dies back completely.
Pruning for Health and Productivity
Pruning is necessary because floricanes will not produce fruit again and compete with new growth for resources if left on the plant. Removing spent floricanes immediately after harvest or during the late winter dormant season redirects the plant’s energy toward the new primocanes, ensuring next year’s fruiting canes are strong.
Removal involves cutting the entire floricane back to the ground level, taking care not to damage new primocanes emerging from the crown. Pruning also improves air circulation. Maintaining an open canopy reduces humidity and allows sunlight to penetrate, keeping the canes healthy.
For many erect-growing varieties, new primocanes are “tipped” or pinched back when they reach 3.5 to 4 feet. This practice, known as summer tipping, encourages strong lateral branches that will bear fruit the following year. Removing the terminal growth redirects the cane’s energy from vertical growth into horizontal branching, increasing the total fruiting area. Leaving four to six of the healthiest primocanes per plant ensures adequate space and light.
Understanding Primocane and Floricane Varieties
Most traditional blackberry types are floricane-fruiting varieties, which follow the two-year cycle of vegetative growth followed by fruiting. These varieties produce a single, heavy crop on the second-year wood in the early to mid-summer. Their predictable life cycle makes the annual removal of spent floricanes a necessary maintenance task.
A newer development is the primocane-fruiting variety, which produces fruit on the first-year canes. These canes develop flowers and fruit on the tips of the primocanes in the late summer or fall of their first year. The fruit quality from this late-season crop can sometimes be reduced by high temperatures in warmer climates.
Primocane varieties offer flexible maintenance. They can be managed for a single, large fall crop by cutting all canes back to the ground during the dormant season. Alternatively, if the canes are left standing, the lower portions of those floricanes will produce a secondary, smaller crop the following summer. This dual-cropping system provides two harvests but may result in smaller overall fruit size compared to a single-crop approach.