How to Plant and Grow Blackberry

Blackberries are delicious, nutrient-rich, and relatively easy to grow, making them perfect additions to your home garden or landscape.

There are three types of blackberries: trailing, erect, and semi-erect. Trailing blackberry needs to be supported by a trellis, fence, or arbor to keep it up and off the ground. Erect blackberry is a hardy, stiff-caned plant that may or may not need support depending on the variety. It tends to spread from new canes emerging from the roots. Semi-erect blackberry types have vigorous, thick, and arching canes that emerge from the crown of the plant. They are typically the latest blackberries to fruit in the summer. 

Blackberry plants have two distinct types of canes: first-year growth called primocanes, and second-year growth called floricanes. Many blackberries produce no fruit on primocanes but on floricanes, which produce flowers and fruit and then die. While blackberry plants have a lifespan between 15 and 40 years, individual canes are biennial.

Where to Plant Blackberry

Plant blackberries in full sun and moist, well-drained, slightly acidic soil. Most varieties get relatively large, so be sure you have room for them before planting. Because blackberry is a big, vigorous plant, it is well-suited to grow in a patch by itself. This is especially true for trailing blackberry varieties with canes that reach 10 feet long or more and need support. Thorny blackberry can serve as a fence or physical barrier when grown around the edges of a property line. Avoid planting it near driveways or walkways. With their lush green foliage and white flowers, blackberries also make a charming addition to an edible landscape.

If you don’t have the right place to plant blackberries in the ground, consider growing them in a large container to control their vigorous growth.

How and When to Plant Blackberry

Regardless of whether you plant bare-root plants or potted plants, plant them in the early spring while the plant is dormant.

When planting bare-root blackberries, dig a hole that is large enough to accommodate the roots. For potted plants, dig a hole large enough to fit the root ball so that the surface of the potting mix is at the same level as the soil. Place the plant in the hole, backfill with original soil and gently tamp it down. Water it deeply and thoroughly. Cut the canes of newly planted bare-root plants to a height of 6 inches, Keep new plants well-watered at all times.

Blackberries can be planted in rows. Space plants 5 to 6 feet apart. If planting more than one row, leave at least 10 feet between rows. Provide a trellis or support for trailing varieties in the second year.

Blackberry Care Tips

The most effort when caring for blackberries is to keep their vigorous growth under control. Other than that, they require very little maintenance.

Light

Plant blackberry plants in a spot that has full sun, at least 6 to 8 hours of direct sun per day. Although the plants will grow in partial or full shade, they are more susceptible to disease and produce fewer and lower quality fruits than when grown in the sun.

Soil and Water

Blackberries prosper in moist, well-drained soil that is rich in organic matter. If your soil has high clay content, amend it liberally with organic matter before planting. The ideal soil pH is between 5.6 and 6.5.

Newly planted blackberries need consistent moisture so their roots get established. Mulching around the plants helps to retain soil moisture. Established plants need 1 to 1.5 inches of water per week. In the absence of sufficient rainfall, they need to be watered, ideally by drip irrigation or a soaker hose, until the soil around the plants gets soaked to a depth of at least 6 inches.

Temperature and Humidity

The zone range of blackberry cultivars varies so choose a cultivar that is adapted to your climate. There are cultivars for climates with subzero winters as well as low-chill blackberries suitable for locations with hot, humid summers.

Fertilizer

After planting, when the plants break dormancy and start growing, lightly fertilize new raspberry plants with a fertilizer that is high in nitrogen, such as blood meal. Repeat this application about six months to two months later.

In subsequent years, use a granular slow-release complete garden fertilizer twice annually, once when the plants start to grow in the spring and again in the summer after the harvest.

Pruning

To keep blackberry plants productive and manageable, prune them twice a year. In the spring, after the plants have started to grow, cut off the top couple of inches of new growth. This is called tip pruning; it encourages your blackberry plants to produce more side branches—which means more fruit.

The second pruning happens in late summer. Remove any canes that have produced fruit; those canes won't produce fruit again the following year. Removing these spent canes will keep your blackberry patch from getting overgrown and will help reduce the incidence of disease.

Pollination

Blackberries are mostly self-pollinating—they produce fruit without the need for pollinating insects. And you only need to plant one cultivar to produce blackberries, as the plants to not require cross-pollination.

Potting and Repotting Blackberry

Because of their size, blackberries are ideally planted in the garden. but planting them in containers is a fallback if the soil is poor or there is no other space. Erect blackberry cultivars work best for container growing. To accommodate the deep roots, you need a 20- to 30-gallon container or a raised bed that is at least 2 feet deep. Fill it with well-draining potting mix or soil. Keep in mind that container plants need more frequent watering than inground plants. Keep the plants well-pruned or they will get out of hand.

Despite its winter-hardiness in cold climates, when grown in pots, the roots of blackberry plants are exposed to the cold. As a protective measure, you’ll need to winterize the pots. To insulate the roots from the cold, wrap the container (not the plant) in several layers of bubble wrap and secure it so it won’t blow off. Remove the insulation as temperatures warm up in the spring.

Pests and Problems 

Blackberries are prone to various diseases, including anthracnose, stem blight, and crown gall. To avoid these diseases, buy disease-free plants from reputable nurseries and plant blackberries away from spots where wild brambles grow, as they are often infected with these diseases. Potential pests are stink bugs and raspberry crown borers.

How to Propagate Blackberry

While it may be tempting to dig up suckers from an existing blackberry patch because they are free and available, you risk introducing a plant to your garden that is infested with a virus or soil that contains plant pathogens or pests. For those reasons it is not recommended to propagate blackberries. Also, keep in mind that many cultivars are protected by plant patents and thus are prohibited from being propagated.

Harvesting

Typically, when a blackberry turns from a shiny black color to dull black, it is ripe. Shiny berries are flavorless and sour.

To pick, gently hold the berry between your thumb and index finger. If it is ripe, it will detach easily from the stem without much pulling; if it doesn’t, give it another couple of days.

Depending on the number of berries on the plant and the weather, harvest blackberries every four days.

Types of Blackberry

Marionberry

This hybrid, also called Marion blackberry (Rubus 'Marion') is a cross between two other types of blackberries, Chehalem and Olallieberry. It was released in 1956 and named after Marion County in Oregon. The conical-shaded fruit ripens in July. The trailing canes grow 4 feet tall and 6 feet wide. Zone 6-9 

'Hall’s Beauty'

The thornless, trailing blackberry cultivar has a bushy growth habit with a mature size of 5 to 6 feet in height and 3 to 4 feet spread. Zone 6-8 

'Columbia Giant'

Valued for their very large berries, these thornless bush-type blackberries grow 5 to 6 feet in height and spread 3 to 4 feet. Zone 6-8 

'Navaho'

Because this erect, fully thornless variety grows so upright and bushy, it does not require a trellis. It grows 4 to 5 feet tall and wide and produces one large summer crop of berries. Zone 5-9 

'Prime-Ark Freedom'

This variety is considered a low-chill blackberry for warm climates. Zone 5-9

'Triple Crown'

This semi-erect thornless blackberry produces one large harvest late in the season in early August. The heat-tolerant bush-type plants grow 4 to 8 feet tall and spread 2 to 3 feet. Zone 5-9