How to grow blackberries

Blackberries are easy to grow and are highly productive, producing bumper crops of delicious fruit from just one plant. Unlike wild blackberries, which are the fruit of brambles and are commonplace in hedgerows and are free to forage, cultivated blackberries are larger and have a better flavour. What's more, cultivated blackberries tend to have a vigorous rather than rampant growth habit, and many varieties are thornless.

Blackberries are a good crop to grow in small gardens as they can be trained vertically, giving lots of productive growth from just a small area of ground.

Where to grow blackberries

Blackberries are hardy and grow throughout the UK. For best results grow in full sun, in fertile soil enriched with compost or well-rotted manure. Most blackberry varieties produce long vigorous stems, known as canes, and need to be trained on a system of wires. This can be against a wall or fence, or a post and wire framework within a garden or allotment. For pots, choose a compact variety that reaches around a metre in height.

How to sow blackberry seeds

To successfully grow blackberries in the UK it's best to buy plants that will fruit within a year or two, rather than raising a blackberry plant from seed, which can take several years to produce fruit.

If you're determined to grow blackberries from seed, buy seed or use seed from the berry of a named variety. Sow at any time of year in pots or trays of loam-based seed compost with added grit or sand to create an open, free-draining mix. Cover the seed lightly with grit. Stand in a cool place outside or in a cold frame and be patient as seedlings can take months to appear. Once large enough to handle, pot up the seedlings individually and grow on before planting out.

How to plant blackberries

Before planting, use vine eyes to attach support wires to a wall, fence or set of sturdy posts. Fix wires horizontally and space them 30cm apart, with the lowest one at 90cm from the ground.

Autumn is the best time to plant blackberries, so they become established in time for the growing season. This is the only time to plant bare-root blackberry plants. Pot grown plants are available all year-round but are still best planted in autumn.

Before planting, cut the stems to 30cm and soak the roots in a bucket of water for a couple of hours. Plant at the same depth as growing previously – on bare-root plants look for the soil 'tide mark' at the base of the stem, and plant pot-grown plants so the top of the rootball sits at soil level. Firm the soil gently around the roots and water thoroughly.

Spacing between plants depends on the ultimate size of a variety, which varies considerably. More compact blackberries like ‘Loch Ness’ can be spaced 2m apart while more vigorous varieties need spacing of up to 4m.

To grow blackberries in pots, choose compact varieties such as ‘Opal’ or ‘Coolaris Late’. Containers should be at least 30cm wide and deep. Use a soil-based potting compost with some added grit for drainage, and plant as per the instructions above. Compact varieties don't need to be trained up support wires.

How to care for blackberries

During the first growing season, water during dry spells to help plants establish. Also in the first year, cut off any flowering shoots to allow the plant to concentrate energy on establishing a good root system. Thereafter, only water plants in periods of drought, unless you're growing them in a pot.

Tie in new stems to the support as and when you need to.

Mulch soil in spring with well-rotted garden compost or manure, keeping the mulch clear of the stems. This boosts the soil’s water-holding capacity and suppresses weeds. Feeding is rarely necessary unless growth looks poor and stunted.

Pot-grown blackberries need regular watering – typically around three times a week during the growing season, and a fortnightly feed using liquid tomato food. In spring, scrape away the top 5cm of compost and replace with fresh, to replenish the natural stock of nutrients.

How to prune blackberries

Prune blackberries annually to remove the canes that have borne fruit, and to create space to tie in new ones that will bear fruit the next year.

Blackberries fruit on two-year-old canes which need to be cut out completely after fruiting, down to soil level. Do this anytime from when fruiting finishes until late winter. New canes should have been produced already and should be tied onto the support framework.

Make the job easier by keeping new canes separated from the fruiting ones. Either gather the new canes into two groups lying on the ground, to left and right, securing with pegs if necessary. Or, tie the fruiting canes onto the framework in a fan shape with a gap in the middle, where you can temporarily tie the new growth, so once the old canes are pruned out, the new ones spread out along the wires.

Pests and diseases

Blackberries are vigorous plants and aren’t susceptible to pests or diseases. Ripe fruit is likely to turn mouldy if left unpicked, or in prolonged wet weather. If this happens early in the fruiting period, pick off the mouldy fruits to avoid them affecting adjacent berries in the fruit cluster. In very hot summers the fruit can be burned.

Birds are likely to eat the ripe fruit. While there’s usually enough to go around, you can protect your crop by growing soft fruit plants in a netting enclosure or fruit cage, or hang bird scarers to deter them. Avoid covering plants with loose netting where birds are likely to get entangled.

What are hybrid berries?

Usually a cross between raspberries and blackberries, these include loganberries, tayberries, tummelberries and boysenberries. Fruiting is usually earlier than blackberries, but they’re grown in the same way.

Harvesting blackberries

For maximum sweetness, let the fruits swell to full ripeness with an even, dark colouring. Gently pull them off the canes and pop them into a shallow dish to avoid crushing them. Watch that the juice doesn’t stain your clothing.

Storing blackberries

Blackberries bruise very easily and won’t keep fresh for long. Store in the fridge where they’ll keep for a few days. They do, however, freeze well. Wash fruits and allow to drain in a sieve or colander. Spread out in a single layer on trays, pop in the freezer, then transfer to bags or tubs after a few hours. This keeps individual fruits separate so you can take a few out as needed.

Preparation and uses

Wash well and remove the hull (stem) before using to make summer-fruit pudding, coulis, smoothies, jam, pies, crumbles and home-made wine. Try this easy recipe for apple and blackberry crumble.

Blackberries varieties to grow

‘Adrienne’ – delicious fruit on strong, thornless stems. Height x Spread: 2.5m x 2.5m

• Buy blackberry ‘Adrienne’ from Otter Farm

‘Coolaris Late’ – extremely compact growth, suitable for containers. H x S: 1.2m x 1.2m

• Buy blackberry ‘Coolaris Late’ from Thompson & Morgan

‘Loch Katrine’ – extra-large and sweet-tasting fruits on a fairly compact growing bush. H x S: 2m x 2.5m

• Buy blackberry ‘Loch Katrine’ from Thompson & Morgan

‘Loch Ness’ – moderate size and vigour, with high yields of large fruits on thornless canes. H x S: 2m x 2.5m

• Buy blackberry 'Loch Ness' from Thompson & Morgan

‘Merton Thornless’ – large crops of well-flavoured berries on thornless stems. H x S: 2.5m x 3m

• Buy blackberry 'Merton Thornless' from Chris Bowers

‘Obsidian’ – one of the earliest to fruit, in July or sometimes even June, and is of moderate size. H x S: 2m x 2.5m

• Buy blackberry 'Obsidian' from Chris Bowers

Frequently asked questions

Can I grow a blackberry bush from a blackberry?

A single blackberry fruit contains multiple seeds that germinate readily, which is why bramble bushes are so abundant in the wild. However, seedlings from cultivated blackberries won’t be the same as their parent. Buying a blackberry plant of a named variety is the best way to guarantee a good plant that crops well.

How long does it take to grow a blackberry?

Blackberries fruit on two-year-old shoots, or canes, and should not be allowed to fruit in the first year after planting to allow the bush to establish fully. So, it takes at least two years from planting for a plant to start producing a crop.