How Do You Prune Raspberry Canes and When Should You Do It?

Raspberry pruning is one of the most straightforward tasks in the fruit garden once you know whether you are growing summer-fruiting or autumn-fruiting varieties — because the two types are pruned at completely different times of year and by different methods. Mixing them up results in cutting down the very canes that were about to fruit, which is a frustrating mistake that costs you a whole season's harvest.

How Raspberries Fruit: Understanding Floricanes and Primocanes

Raspberry canes grow for one year as primocanes — vigorous, usually reddish or greenish first-year canes. In their second year, they become floricanes: they produce flower clusters and fruit, then die. New primocanes grow from the base each season to replace them. Summer raspberries fruit on the previous year's floricanes in June and July. Autumn raspberries (primocane-fruiting varieties) fruit on the current season's new canes from August to October.

Pruning Summer Raspberries

After summer raspberries finish fruiting, cut all the canes that fruited down to ground level. They have completed their cycle and will not produce again. Do not delay: getting rid of the old canes quickly improves air movement and reduces the risk of cane blight and botrytis spreading to the new primocanes that are already growing up. Tie the new canes in to the support wires, spacing them about 10 cm apart, and shorten any that extend above the top wire in late winter by cutting back to a healthy bud.

Pruning Autumn Raspberries

Autumn raspberries are much simpler to manage. In late winter — February is ideal — cut all canes down to ground level. Every single cane, regardless of age or appearance. New primocanes will push up from the roots in spring, and these will fruit in their first year from August onwards. This simple technique is one of the reasons autumn-fruiting varieties are so popular with beginners: there is no complexity in identifying which canes to keep and which to remove.

How Many Canes to Keep

After pruning, thin the remaining canes so they are spaced about 8–10 cm apart. A well-established row should have roughly six to eight strong canes per metre of row. Remove the weakest canes at ground level, keeping the strongest. Overcrowded canes shade each other, reduce air circulation, and produce smaller fruit. If your row is spreading outward from the original planting position, cut back canes growing outside the designated row width to keep the bed manageable.