Blackberries (Rubus spp.)
Blackberries are one of the bramble fruits that originated from native wild species. These easy-to-grow fruit shrubs grow long canes that produce juicy berries. Blackberries need time to grow and become established in the garden before producing large crops of berries. The first blackberries will grow on two-year-old canes.
How to Grow Blackberries
Before buying blackberry plants, take time to read about the different varieties to find the best fit for your garden space. Blackberry cultivars are either trailing, erect or semi-erect which refers to whether their canes grow long or upright. It also makes a difference in how they’ll need to be supported, trellised and trained.
Some blackberries have thornless canes like ‘Apache’, ‘Arapahoe’, ‘Black Satin’, ‘Ebony King’, ‘Ouachita’, and ‘Triple Crown’. Other blackberry cultivars, like ‘Darrow’ and ‘Shawnee’ have thornier stems.
Find a good-sized area that gets full-sun with slightly sandy or well-draining soil. Amend the soil deeply with organic matter to provide a good planting bed.
Trailing blackberries grow best on a two-wire trellis that supports the long canes. Erect or semi-erect blackberry cultivars also need support, either by staking individual plants or growing them along a single wire fence.
The space between plants depends on the type of blackberries planted. For erect cultivars, plant blackberries about 3 feet apart and in rows that are 5-8 feet apart. Semi-erect types will need more space, about 5-6 feet apart. Trailing blackberries are planted 4-6 feet apart.
Place a soaker hose or drip line after planting to make sure water will go directly to the roots.
Add a layer of organic mulch, like straw or dry untreated grass clippings, 4-6 inches thick around the base of plants, but keeping clear of touching the stems.
Encourage good root development, especially the first year, with frequent, deep watering. Plants may need to be watered several times a week during the first year, but weekly after that. Use a balanced fertilizer to feed plants in spring as soon as new growth begins to appear.
The key to good crops of blackberries is pruning. If pruning is neglected or done haphazardly, the canes will not produce berries. Only cut blackberries down in the fall and only cut the canes that grew fruit that season.
Another pruning tip is to cut the top 6-12 inches of each cane the first year to encourage side branching for the second year.
In summer, wait to harvest blackberries until the fruit easily comes off the plants. Look for berries that have turned from shiny to dull and harvest as soon as they’re ready or they’ll dry on the cane.
Companion Plants for Blackberries
- Bee balm
- Borage and other flowering herbs
- Chives and garlic
Materials for Blackberry Success
- Compost or other organic matter for amending the soil
- Organic mulch
- Sturdy support or trellis system
- Soaker hose or drip irrigation system
- Balanced fertilizer
- Hand pruners