Raspberry and blackberry canes are biennial: a cane grows its first year (a primocane), fruits its second year (a floricane), then dies. On summer-bearing types, after harvest cut out only the spent floricanes, at ground level, and keep the current year's primocanes - they are next year's crop. Cutting every cane down on a summer-bearing plant removes next year's fruit. Ever-bearing (primocane-fruiting) types fruit on first-year canes and, grown for a single fall crop, can instead be cut wholesale close to the ground in winter.
Promising · suboptimal if ignored → advise
How it works
Each cane lives two years while the crown persists: a vegetative primocane in year one becomes the fruiting floricane in year two, and a floricane dies after fruiting - it will not fruit again or survive another winter. Next year's fruiting wood is therefore this year's primocanes, so removing them removes the crop. The spent floricanes are cut at ground level because dead stubs left standing can harbor canker-causing fungi.
What to do about it
After harvest, or while the plants are dormant, cut the canes that fruited out at ground level and leave the current primocanes standing; thin crowded primocanes so the keepers grow stout. On an ever-bearing type grown for one fall crop, cut all canes very close to the ground in winter instead.
How much it matters: No figure is stated or invented. Keeping the primocanes preserves next year's crop outright; removing the dead floricanes flush with the ground also removes overwintering cane-disease harbor. Because which canes to cut is the gardener's annual choice, the rule advises rather than warns.
The evidence
Evidence: confirmed against 2 sources in the research-based literature.
the 2 sources
Univ. of Maryland Extension, 'Growing Raspberries and Blackberries in a Home Garden', extension.umd.edu/resource/growing-raspberries-and-blackberries-home-garden (read 2026-08-22): 'In the second growing year, those one-year-old canes, now called floricanes, produce flowers and fruit on main stems and laterals (side branches)'; 'Floricanes die after fruiting and must eventually be removed because they will not produce another harvest or survive a second winter'; 'When plants are dormant, remove the dead floricanes that fruited the previous season'; 'When removing dead, fruited canes or excess primocanes, make the cuts at ground level so that the dead stubs do not protrude where they can harbor canker-causing fungi'; 'Primocane-bearing raspberry and blackberry cultivars produce fruit on first-year canes.'
Univ. of Illinois Extension, 'Pruning and Training Raspberries', extension.illinois.edu/small-fruits/pruning-and-training-raspberries (read 2026-08-22): 'primocanes are first year growth and in second year they grow into floricanes which bear fruits'; 'Floricanes are cut after harvest'; 'Primocanes that will bear fruits the following year are thinned to avoid competition'; 'For a single late season crop harvest, canes are cut very close to the ground in December to February.'
Where this rule stops
A STANDING CULTURAL ADVISORY (trigger.kind always), gated by applies_to to the two bramble species. It surfaces on the raspberry and blackberry pages and can be cited by the planting guides; it gates nothing and docks no score - the app cannot see a cane's age or a cultivar's bearing type. The rule states the summer-bearing (floricane-fruiting) default and carries the primocane-fruiting exception honestly in prose; it does not try to detect which type a plant is. Both sources are raspberry-and- blackberry or raspberry-specific; UMD covers both species and the ground-level/canker point, Illinois independently confirms the cycle and the after-harvest cut for raspberry.
Plants this fires on
Change history
Every change to this rule is one commit. This is what the project's version history records — the date and the reason — not a summary of it.
- bramble floricane pruning (verified, UMD + Illinois)
Cite this page
Milpa Gardens. "Raspberry and blackberry canes are biennial: a cane grows its first year (a primocane), fruits its second year (a floricane), then dies. On summer-bearing types, after harvest cut out only the spent floricanes, at ground level, and keep the current year's primocanes - they are next year's crop. Cutting every cane down on a summer-bearing plant removes next year's fruit. Ever-bearing (primocane-fruiting) types fruit on first-year canes and, grown for a single fall crop, can instead be cut wholesale close to the ground in winter." Evidence grade: Promising. https://milpa.garden/rules/raspberry-blackberry-canes-biennial-cane-grows-first/
A garden-planning corpus: every claim states its evidence grade and links its sources on the page. Cite it with the grade, and add the date you read it.