The method you use to prune or train will depend on the type of blackberry plant. Essentially, there are two types of blackberry: erect, and trailing, and there are many varieties available in both of these types. Erect varieties have stiff canes that are upright and arching. They can be grown with or without a trellis as a hedge or shrub border. Trailing blackberries have flexible canes that must be tied to a trellis or maybe a fence. All blackberry plants produce what are called "primocanes." which eventually become "floricanes." Additionally, there are new hybrids, called "primocane-fruiting" blackberry, that require a different pruning method. Scroll down to find pruning instructions for these hybrids.
Pruning Terms
Learning to master the art and science of pruning blackberry plants takes a little time and practice. It helps to familiarize yourself with a few terms before reading pruning instructions.
Primocane: These are the green shoots that emerge ever year that mature into a woody-textured cane by late fall.
Floricane: This is the flowering cane that will produce fruit and which was a primocane in the previous growing season.
Cane: The main, erect growing shoots (trunks).
Lateral Shoot: The leafy green growth that develops from lateral buds along the cane, Lateral shoots grow rapidly when the main cane is tipped.
Node: - The thickened portion of a cane where the leaf is attached and a bud is located.
How To Prune Blackberries
Blackberries produce main upright branches that are called "canes." New shoots will emerge every year that are called "primocanes." These primocanes then mature into "floricanes" in the fall which will flower and produce fruit the following season. Once the fruit has been harvested, the floricanes will eventually die. All spent floricanes should be removed from the plant. By removing the spent floricanes you'll be providing more space for new primocanes to grow the following year.
First Year Pruning: Erect primocanes can be left unpruned during the first year.
After First Year Pruning:
- Take time to observe the plant and determine what canes need to be pruned.
- During the growing season, usually in June or July, use your fingertips to tip back each developing, new primocane to 48 inches. By tipping back the ends of the canes it releases growth hormones, which stimulates new growth from the lateral buds along the cane. Increasing the amount of lateral canes (branches) will increase the number of flowers, and therefore the quantity of fruit produced.
- With more aggressive varieties, tip lateral shoots back in the early spring of the following year to help restrict excessive growth.
- Do not prune the floricanes before the fruiting season unless they are damaged or diseased.
- When the fruiting season is over, use lopper pruners to cut out spent flouricanes at their base. Remove all pruned material from around the plants and discard.
When is the best time to prune primocane-fruiting erect blackberries?
There are a few new hybrid blackberries (Prime Jim, Prime Jan) that actually produce fruit on primocanes (new shoots/canes) in fall that grew during the summer. This is different than standard erect blackberries that only produce fruit on primocanes in the following year. Regarding the primocane-fruiting varieties, once fruiting is completed and frost has occured, all primocanes can be pruned or mowed off. Or you can wait until late winter or early spring and prune all the canes before new growth begins to emerge.
Are there different pruning methods for throny and thornless blackberry varieties?
Both types are general pruned using the same method. It's just that the thorny canes are more difficult to handle. It's a good idea to wear long "rose-pruning" gloves and a thick, long-sleeved shirt when pruning thorny varieties. On the other hand, thornless varieties have smooth canes and are easier to prune. Thorny varieties tend to produce more canes and more vegetation than do thornless varieties.
