Overview
What blackberries need, when they crop, and whether you have room for them.
A blackberry plant is two plants in one: the roots and crown live for decades, but each cane lives just two years, growing in the first and fruiting in the second. Understand that and pruning follows: cut out the canes that fruited, tie in the new ones. Choose a thornless garden variety and you get larger, plumper, sweeter fruit than the hedgerow’s, without the scratches.
Quick facts
- Botanical name
- Rubus fruticosus
- Soil pH
- 5.5 – 7.0
- Height
- Up to 250 cm (98 in)
- Propagation
- Layering, Cutting
Growing details
- Frost sensitivity
- Frost hardy
Growing calendar
- Plant out: January, February, March, November, December
- Harvest: July, August, September, October
- Prune: January, February, August, September, October, December
While dormant in the UK; in cold-winter US regions, early spring. Summer-bearing types midsummer to early autumn; primocane types into autumn. Cut out fruited canes after harvest or in winter; tip erect canes in summer.
Is this plant right for you?
- Perennial fruit
- Needs support
- Frost hardy
- Crops for many years
- Thornless varieties
- Compact types for pots
- Needs space
Good to know
Plan for support early: this plant needs a stake, cage or frame once it gets going. It stands frost, so it can go out earlier than tender crops.
Before You Grow
Choose a type and a variety for your space and climate, then put up the support before you plant.
Check each variety’s eventual spread: 1 m (3 ft) to 4 m (13 ft) is a big difference.
What you need
Certified, disease-free plants
Pot-grown or bare-root, from a nursery. Suckers dug from an old patch can carry viruses and pests.
A support
Horizontal wires on a wall, fence or posts, put up before planting. See training and pruning.
A sunny spot with room
Up to 4 m (13 ft) per plant for vigorous types. See where they grow best.
Compost for mulching
A spring mulch every year. See feeding.
Secateurs, twine and thick gloves
For tying in and pruning; gloves for thorny types.
Netting or a fruit cage
Birds love the fruit. See pests.
Choose your blackberries
Garden blackberries give larger, plumper, sweeter fruit than wild brambles. Three choices shape how you grow them.
Growth habit. Trailing types make long, floppy canes, up to 4.5 m (15 ft), that must be tied to a support. Erect types have stiff, upright canes and sucker from the roots, so they form a hedgerow. Semi-erect types are the most vigorous, with thick, arching canes. All benefit from some support.
Thorny or thornless. Thornless varieties make pruning, training and picking far more pleasant, and many modern varieties are thornless.
Summer or autumn fruiting. Most blackberries are floricane-fruiting: canes grow one year and fruit the next. Primocane-fruiting (everbearing) types also fruit at the tips of first-year canes in late summer or autumn, and can give two crops a year.
Size. Vigorous varieties spread up to 4 m (13 ft); compact ones such as ‘Little Black Prince’ reach about 1 m (3 ft) and suit a pot.
Hybrid berries. Tayberries, loganberries and boysenberries are blackberry crosses, usually earlier, grown the same way.
Climate. Choose varieties suited to your winters: trailing types and the hybrids are the least cold hardy.
Varieties compared
-
Obsidian
- Type
- Blackberry
- Size (H x S)
- 2 x 2.5 m (6½ x 8 ft)
- Notes
- One of the earliest: July, sometimes June
-
Loch Ness
- Type
- Blackberry, thornless
- Size (H x S)
- 2 x 2.5 m (6½ x 8 ft)
- Notes
- Large fruit, high yields
-
Loch Katrine
- Type
- Blackberry
- Size (H x S)
- 2 x 2.5 m (6½ x 8 ft)
- Notes
- Extra-large, sweet fruit; fairly compact
-
Adrienne
- Type
- Blackberry, thornless
- Size (H x S)
- 2.5 x 2.5 m (8 x 8 ft)
- Notes
- Good flavour on strong canes
-
Merton Thornless
- Type
- Blackberry, thornless
- Size (H x S)
- 2.5 x 3 m (8 x 10 ft)
- Notes
- Large crops
-
Coolaris Late
- Type
- Blackberry, compact
- Size (H x S)
- 1.2 x 1.2 m (4 x 4 ft)
- Notes
- For containers
-
Prime-Ark Freedom
- Type
- Blackberry, erect, primocane
- Size (H x S)
- Varies
- Notes
- Thornless; autumn crop, can crop twice
-
Tayberry
- Type
- Hybrid
- Size (H x S)
- Vigorous
- Notes
- Red fruit; July and August
-
Boysenberry
- Type
- Hybrid
- Size (H x S)
- Moderate
- Notes
- Dark fruit, wild-blackberry flavour; July
Sizes from Gardeners’ World; they vary with site and pruning. In a small garden, choose by spread first, then by season.
Where blackberries grow best
Blackberries are long-lived: a planting crops for 15 to more than 40 years (OSU). Choose the spot with care.
Site. Sunny and sheltered, against a wall or fence, or along a row of posts, with room for the plant’s full spread. Against a wall, plant at least 30 cm (1 ft) out from the base.
Space. RHS spaces moderately vigorous plants 2.5 to 3.5 m (8 to 11 ft) apart and very vigorous ones 4 m (13 ft); compact types such as ‘Loch Ness’ 2 m (6½ ft). US extensions plant erect types 75 cm to 1.2 m (2½ to 4 ft) apart in a hedgerow and trailing types 1.8 to 2.4 m (6 to 8 ft), with rows about 3 m (10 ft) apart.
Cold. Most are hardy. Trailing types and hybrid berries are the least cold hardy; in cold or exposed gardens, leave their new canes on the ground over winter and tie them up in late winter.
Weeds first. Clear perennial weeds before planting: they are hard to control afterwards.
Sun. Full sun gives the best crop and the healthiest plants.
Shade. The sources differ. The RHS says blackberries fruit in light shade, and OSU that they tolerate partial shade with a lower yield and poorer fruit. Clemson advises against planting in part shade at all.
Very hot summers can scorch the fruit (Gardeners’ World).
- Planting life
- 15 to 40 years or more
- Spread
- 1 to 4 m (3 to 13 ft) by variety
- Yield
- About 4.5 to 9 kg (10 to 20 lb) a plant (NC State)
Soil
Blackberries want fertile, well-drained soil with plenty of organic matter. Sandy loam and clay loam suit them.
Drainage. Avoid ground that waterlogs; on heavy clay, root rot is more likely, so build a raised bed (UMD, NC State). OSU finds most blackberries tolerant of wet, heavy soil.
pH. Slightly acid: about 6.0 to 6.5 is ideal, and 5.5 to 7 is workable (UMD). Test the soil a season or more ahead so there is time to correct it with lime or sulfur.
Preparation. On poor soil, mix a bucketful of compost or well-rotted manure into the soil from the planting hole.
Planting
Plant while dormant, cut the canes back hard, and let the first year build roots.
Buy certified, disease-free plants rather than digging up a neighbour’s suckers.
When to plant blackberries
Plant while the plants are dormant.
In the UK, mid-autumn to early spring; Gardeners’ World prefers autumn, so plants settle before the growing season. Bare-root plants are only sold in this window. Pot-grown plants can go in at any time except hot, dry spells.
In cold-winter US regions, plant in early spring, about four to six weeks before your last frost (Clemson), or as soon as the soil can be worked. In milder areas, NC State plants in spring or autumn.
Plant on arrival. If you can’t, heel bare-root plants in by covering their roots with moist soil.
How to plant blackberries
Put the posts and wires up first: it is far harder once the canes are growing.
-
Soak bare-root plants
Stand the roots in a bucket of water for a couple of hours.
-
Dig a wide, shallow hole
Big enough to spread the roots out. On poor soil, mix compost into the soil you took out.
-
Set the plant at the right depth
Pot-grown plants at the level they grew in the pot. Bare-root plants with the uppermost roots about 5 cm (2 in) below the surface, or at the soil mark on the stem.
-
Firm in and water well
Firm the soil around the roots to remove air pockets, then water thoroughly.
-
Cut the canes back
To healthy buds 15 to 30 cm (6 to 12 in) from the ground: 15 cm (6 in) says OSU, 20 to 25 cm (8 to 10 in) the RHS, 30 cm (12 in) Gardeners’ World. Strong new canes grow from the base in spring.
-
Hold off the fertiliser
NC State waits three or four weeks after planting; UMD eight.
Care
Tie in new canes, prune out old ones after harvest, and water well while the fruit swells.
Keep the new canes separate from the fruiting ones so pruning time is obvious.
Care through the year
First year
Water: in dry spells · Fruit: none, usually
Water, weed and tie in new canes as they grow. See training and pruning.
Spring
Mulch: compost, clear of the stems · Feed: as growth starts
Mulch and feed; separate new canes from fruiting ones. See feeding.
Summer
Water: about 2.5 cm (1 in) a week · Pick: every few days
Tip erect canes; water well while fruit swells; net against birds. See watering.
After harvest
Prune: fruited canes to the base · Feed: again, in some regions
Cut out the canes that fruited and tie in the new ones. See training and pruning.
Winter
Prune: side shoots · Protect: tender types in cold areas
Shorten side shoots and tidy the canes while dormant.
Watering blackberries
New plants have small root systems and dry out easily: water them well, several times a week in dry weather, through their first season.
Established plants are fairly drought tolerant, but the fruit is mostly water, so they need steady moisture while it develops: about 2.5 cm (1 in) a week, and more in fruit (OSU gives 2.5 to 4 cm, or 1 to 1½ in). In the UK, the RHS and Gardeners’ World water established plants only in long dry spells.
How. At the base: drip lines or a soaker hose are ideal, and keep water off the fruit, which rots in wet weather.
Mulch holds the moisture and keeps weeds down.
Feeding blackberries
Mulch every spring with compost or well-rotted manure, keeping it clear of the stems. The RHS finds regularly mulched plants need no other feeding unless crops are poor or leaves show deficiency.
Where soil is hungrier, US extensions feed in spring as growth starts and again after harvest (Clemson, NC State). Nitrogen is the main need after planting (OSU).
Reading the leaves. Healthy plants have dark green leaves. Pale green or yellow older leaves suggest a shortage of nitrogen (OSU).
In pots, Gardeners’ World gives a liquid tomato feed every fortnight and replaces the top 5 cm (2 in) of compost each spring.
Training and pruning
Each cane lives two years: it grows in the first (a primocane) and fruits in the second (a floricane), then dies. Pruning is mostly cutting out canes that have fruited and tying in the new ones.
The support. Horizontal wires on posts, a wall or a fence. The RHS spaces wires 45 cm (18 in) apart from 45 cm (18 in) above the ground; Gardeners’ World 30 cm (1 ft) apart from 90 cm (3 ft). Erect types do well on a T-trellis, a wire on each side of the row.
Keep old and new apart. Fan the fruiting canes out along the wires and tie the new canes loosely in a bundle in the middle, or along the ground, so they never tangle.
After harvest, cut every fruited cane at its base, taking care not to cut the green new canes, then spread the new canes along the wires in their place. You can leave this until late winter.
Tipping erect types. When new canes reach 75 to 90 cm (30 to 36 in), or the top wire, cut off the top 5 to 10 cm (2 to 4 in). This makes them branch, and the branches carry next year’s fruit. In winter, shorten these side branches to 30 to 40 cm (12 to 16 in).
Thin. Keep the strongest new canes: Clemson keeps three to six per plant. Remove root suckers of erect types that stray outside a 30 cm (12 in) row.
Primocane types can be cut to the ground in late winter for one autumn crop, or pruned like summer-fruiting types for two crops.
Blackberries in containers
Compact varieties such as ‘Little Black Prince’, ‘Opal’ or ‘Coolaris Late’ grow in pots without wires.
Pot size. Blackberries root deeply. Gardeners’ World uses at least 30 cm (1 ft) wide and deep, the RHS at least 45 cm (18 in). OSU uses 75 to 115 L (20 to 30 gal) and at least 60 cm (2 ft) deep for primocane types.
Compost. Loam-based, with grit for drainage.
Care. Water regularly, about three times a week in the growing season (Gardeners’ World). Feed fortnightly, and replace the top layer of compost each spring. OSU keeps no more than four new canes per pot.
Problems
Healthy plants have few problems. Birds, grey mould and, in some areas, spotted wing drosophila are the main ones.
Common blackberry problems
These are growing problems, not pests or diseases.
No fruit in the first year
- Normal
Canes fruit in their second year. Expect a small crop the year after planting and a full one the year after that. Only primocane types fruit in the planting year.
Sour, shiny berries
- Picked too early
Shiny black berries are high in acid. Wait until they turn dull black. See harvesting.
Canes dying back from the tip, no side shoots
- Cold damage
Winter cold kills the tips first, and damaged canes don’t fruit. Choose hardy types, and in cold areas keep tender types’ canes on the ground over winter.
Scorched fruit
- Heat
In very hot summers, exposed fruit burns (Gardeners’ World).
A tangle that crops poorly
- Not pruned
Unpruned plants become a thorny mass that fruits less and is hard to pick. See training and pruning.
Twisted, damaged growth near weeded areas
- Weedkiller
Blackberries are sensitive to glyphosate. Keep weedkillers well away from the plants (OSU).
Common pests
Birds
They take ripe fruit. Grow plants in a fruit cage, or net them with taut netting held above the fruit on canes or poles, so birds can’t get tangled.
Spotted wing drosophila
OSU calls it the most important blackberry pest where it occurs. A small vinegar fly lays eggs in colouring fruit and larvae feed inside. Pick often, don’t leave overripe fruit on the plant, and consider fine exclusion netting to keep the flies off (OSU).
Red berry mite
Makes some drupelets stay hard and red while the rest of the berry ripens, mainly on late summer-bearing types.
Aphids and spider mites
Sap-suckers on shoots and leaves; spider mites stipple the leaves. Natural enemies and removing affected shoots often keep them down.
Crown borers
Larvae bore into canes and crown; badly infested plants die. Remove and destroy affected plants.
Common diseases
Clean, certified plants, good airflow, prompt pruning and regular picking reduce these problems.
Grey mould (botrytis)
Fuzzy, rotting fruit in wet weather, the most common fruit rot. Pick mouldy fruit off at once, keep water off the fruit, and pick often.
Rusts
Yellow or orange spots under the leaves, which can spread to the fruit. Clear affected growth; ask your local extension about control.
Cane and leaf spots
Purple blotches on canes and spots on leaves, mainly on trailing types. Remove fruited canes promptly after harvest.
Crown gall
Rough swellings on crown or canes, which may split. It persists in soil for years: remove infected plants, disinfect tools after pruning, prune only in dry weather, and don’t replant affected ground (OSU).
Root rot
Canes die in midsummer and fruiting shoots collapse, on wet, heavy soil. Plant in well-drained soil or a raised bed.
Viruses
Start with certified virus-free stock rather than suckers from an old patch, which can carry them (OSU).
Harvest & Use
Pick dull-black berries every few days, gently, and chill them fast.
Harvesting blackberries
Blackberries ripen from midsummer to early autumn, depending on variety; primocane types carry on into autumn. Harvest from one variety lasts about two to three weeks or longer, depending on variety and weather (Clemson, NC State).
When. Pick when the berries turn from shiny black to dull black: that is when they are sweetest. They don’t ripen further once picked.
How. Hold the berry and ease it up or down rather than pulling: a ripe one breaks away with its core. Lay them in a shallow bowl, no more than two or three berries deep.
How often. Every few days, more often in warm or wet weather. Regular picking keeps pests and rot down. In dry weather pick after the dew has dried, in the cool of the day.
When to expect a crop. A small crop the year after planting, a full crop the year after that.
- Dull black means ripe; shiny black means sour.
- Ease the berry off; don’t pull.
- Pick every few days, into shallow containers.
Storing and using blackberries
Blackberries bruise easily and don’t keep long.
Chill them quickly. Don’t wash berries before storing (wet fruit decays faster), and refrigerate as soon as you pick (OSU): the faster the heat goes, the longer they keep. In a breathable container, two or three berries deep, they last a few days. For longer keeping, NC State picks some shiny black berries: less sweet, but longer lasting.
Freeze well: spread washed, drained berries on trays, freeze, then bag them so they stay separate.
Uses. Fresh, in crumbles, pies, summer puddings, smoothies, jam, jelly and home-made wine.
Propagation
Root a cane tip in the soil, or take root cuttings, from healthy plants only.
Propagating blackberries
Tip layering keeps the new plant attached while it roots. In mid to late spring, bend the tip of a vigorous young cane down to the soil and bury or peg it; it roots and makes a new plant you can cut free and move (RHS).
Root cuttings. Lay sections of root horizontally and cover them with soil; they send up new shoots (Clemson).
Suckers from erect types root readily, but digging them from an old patch can bring in viruses and soil pests, and many varieties are patented, so propagating them may not be legal (OSU).
Seed germinates readily but seedlings of cultivated blackberries won’t match their parent and take years to fruit.
More to Explore
Quick answers, guides that pair well with blackberries, and the sources behind this one.
Frequently asked questions
When do blackberries fruit after planting?
Most give a small crop the year after planting and a full crop the year after that. Primocane types can crop in the first autumn.
Do blackberries fruit on old or new wood?
Most fruit on canes that grew the previous year. Primocane types also fruit on this year’s canes, in late summer and autumn.
When should I prune blackberries?
Cut out fruited canes after harvest or in winter, tip erect canes in summer, and shorten side shoots in winter. See training and pruning.
Do blackberries need a trellis?
Trailing types must be supported; erect types benefit from it. Compact pot varieties don’t need wires.
How far apart should I plant blackberries?
From about 1 m (3 ft) for erect types in a row up to 4 m (13 ft) for vigorous trailing ones. See where they grow best.
Can I grow blackberries in a pot?
Yes, a compact variety in a deep pot. See blackberries in containers.
How do I know when blackberries are ripe?
When they turn from shiny to dull black and come away easily.
Do I need two blackberry plants?
No: blackberries don’t need cross-pollination. More varieties just lengthen the season.
Why are some drupelets still red?
Often red berry mite, on late summer varieties. See pests.
How long do blackberry plants live?
The roots and crown live 15 to 40 years or more; each cane lives two.
Related guides
Sources
- How to grow blackberries and hybrid berries (opens in a new tab) Royal Horticultural Society
- Growing blackberries in your home garden (EC 1303) (opens in a new tab) Oregon State University Extension Service
- Start growing thornless blackberries (opens in a new tab) University of Maryland Extension
- Blackberry (opens in a new tab) Clemson Cooperative Extension, Home & Garden Information Center
- Training and pruning blackberries (opens in a new tab) University of Illinois Extension
- Blackberries for the home garden (opens in a new tab) NC State Extension
- How to grow blackberries (opens in a new tab) BBC Gardeners’ World