How to grow Blackberry in New Zealand
Garden blackberries are named, well-behaved cultivars, many of them thornless, that give heavy crops of large, glossy fruit from December to March. They are a very different plant from the wild bramble, which is one of New Zealand's most widespread weeds. Grow a named thornless variety on a trellis, keep it tidy, and you get the fruit without the problem.
📖 Our full guide: How to Grow Blackberry in New Zealand
At a glance
When to plant by region
| Region | When to plant | Regional note |
|---|---|---|
| Northland | June to August | |
| Auckland | June to August | |
| Waikato & Bay of Plenty | June to August | |
| Central North Island | June to August | |
| Wellington & Lower North Island | June to August | |
| Nelson & Marlborough | June to August | |
| Canterbury | June to August | |
| Otago & Southland | June to August | |
| Central Otago | June to August |
Not to be confused with: Wild blackberry or bramble (Rubus fruticosus), a thorny, suckering weed of stream and bush edges listed by Weedbusters. Boysenberry, a blackberry hybrid with dark wine-purple fruit.
Where to plant
Plant in full sun in deep, well-drained soil with plenty of organic matter, sheltered from strong and hot, dry winds. Good airflow helps keep disease down. Rows running north to south give the canes the most sun. Put the trellis or wires in place at planting time.
Wild blackberry is a serious weed in New Zealand. It forms dense, thorny thickets along streams, bush edges and in open country, spreading by rhizomes and by birds carrying the seed. It is not on the National Pest Plant Accord, and it is so widespread that councils such as Greater Wellington leave its control to landowners, but some regional pest management plans set rules for it, so check yours. Grow only named thornless cultivars, and do not let canes root or escape beyond the garden.
- All regions: garden blackberries are hardy and grow New Zealand wide. Plant dormant canes from June to August.
- In hot, sunny districts, strong heat and sun can spoil ripening fruit, so shade the row with shade cloth in extreme spells.
Choosing a variety
- Black Satin: thornless and self-fertile, with erect, non-suckering canes to about 1.5 to 1.8 m and large, glossy, sweet-tart fruit ripening in February and March. Tolerates heat and grows New Zealand wide.
- Navaho: erect and thornless, with large, firm, sweet fruit from mid December, and good tolerance of both heat and cold.
How to plant
- Set up a trellis or two or three wires between posts before planting.
- Dig in plenty of compost or organic matter.
- Plant dormant canes about 1.5 m apart, in rows 2 m apart, at the depth they were growing.
- Tie the canes loosely to the wires with soft twine.
- Water in well and mulch.
Watering and feeding
Keep the soil moist, especially while the fruit is developing and ripening, and mulch every spring to hold moisture. Water at the base rather than over the plants to reduce botrytis.
Feed in spring with a fertiliser for berries or fruit, following the rate on the pack.
Pruning and care through the year
- Blackberries fruit on canes that grew the previous year. Through spring and summer, tie in the strong new canes and remove thin, weak and wandering ones.
- In late summer or early autumn, cut about 10 cm off the tips of the new canes to encourage fruiting side shoots.
- After harvest, cut the canes that have fruited off at ground level, in autumn, or in winter in cooler, drier areas.
- A copper and oil spray in winter helps keep the plants healthy.
- Net the plants as the fruit colours if birds are a problem.
Harvesting
Pick when the berries are fully black, plump and come away with the gentlest tug; berries that resist are not ripe. Fruit ripens over several weeks, so pick every couple of days.
Blackberries keep only 2 to 3 days in the fridge. Freeze them in a single layer on a tray, then bag them, for months of use.
Growing in pots
A compact, erect variety can be grown in a large pot at least 40 cm wide with a frame or obelisk for support. Use a quality potting mix, keep it well watered, and feed in spring.
Using it
Eat blackberries fresh, or use them in crumbles, pies, jam, jelly, juice and smoothies.
Companion planting
Flowers around a blackberry row bring in the bees that pollinate it.
Good companions
- Borage Its blue flowers are loved by bees, which pollinate the berries.
- Marigold Brings beneficial insects to the row.
- Nasturtium A ground cover that flowers for months and attracts insects.
- Tansy A strong-smelling herb traditionally grown near berries.
Pests and diseases
Birds take the most fruit. Grey mould in wet weather is the main disease.
Pests to watch for
- Birds Ripe fruit pecked or stripped. Net the row as the fruit colours.
- Spider mite Stippled, yellow, dried-out leaves, sometimes with fine webbing underneath.
- Aphids Clusters of small insects on new shoots.
- Caterpillars Holes in the stem end of the fruit, grubs in the fruit, and leaves rolled together.
Diseases to watch for
- Botrytis Fruit with grey, fuzzy mould that turns soft and watery. Remove affected fruit and thin leaves for airflow.
- Downy mildew Purple or black patches on leaves and stems, and deformed, shrivelled fruit.
- Rust Orange pustules on leaf undersides.
- Root rot Wilting canes and yellowing leaves in wet, poorly drained soil.
- Anthracnose
Common questions
Is it legal to grow blackberries in New Zealand?
Yes. Wild blackberry is a widespread weed but it is not on the National Pest Plant Accord. Some regional pest management plans have rules about it, so check your regional council's plan, and grow named thornless cultivars that do not sucker.
When do blackberries fruit in New Zealand?
From about mid December for early varieties such as Navaho to February and March for Black Satin.
How do I prune blackberries?
Cut the canes that have fruited off at ground level after harvest. Tie in strong new canes through the season, remove weak ones, and tip the new canes by about 10 cm in late summer.
Do I need two blackberry plants?
No. Garden blackberries such as Black Satin are self-fertile, but they need bees to pollinate the flowers.
Why are my blackberries going mouldy?
That is botrytis, or grey mould, in wet or humid weather. Pick ripe fruit promptly, remove mouldy fruit, and thin the leaves for better airflow.
Can I grow blackberries in a pot?
Yes, a compact, erect thornless variety in a pot at least 40 cm wide with a frame for support. Keep it well watered.
Sources we checked: Yates NZ: How to grow blackberries; Yates NZ: Common problems of blackberries; Incredible Edibles (Tharfield Nursery): Berryfruit; Waimea Nurseries: Blackberries; Weedbusters: Blackberry; Greater Wellington: Pest plants.