Growing Blackberries

Growing raspberries and blackberries takes planning

Bill Sevier Ask a Master Gardener

Saturday, January 14, 2017

Q: Do blackberries and raspberries grow well in Oklahoma? How does one get started? M.E., Tulsa.

A: Blackberries are the easiest of all fruits to grow in Oklahoma. Raspberries are similar; the plants grow well, but the weather — spring freezes and high heat in summer — limits berry production. As a group they are called “brambles,” and the discussion below applies to both. There are hybrids between these two such as boysenberries, dewberries and others.

Although easy to do, establishing a berry patch includes more than planting a few transplants in an existing garden bed in your backyard. A good place to start planning is with OSU fact sheet HLA-6215, “Blackberry and Raspberry Culture for the Home Garden.” This document discusses the essentials, which are site selection and preparation, variety choice, propagation and planting, and general care — mulching, fertilizing, irrigation, training and pest control. The techniques of harvesting are also discussed.

The berries need at least six to eight hours of sun. They tolerate a wide range of soils if well-drained. For wet areas or heavy clay soil, use raised beds. You should perform a soil test to get an idea of what amendments are needed. Blackberries prefer a pH of 5.5 to 6.5 (slightly acidic), and all beds will benefit from composted organic material tilled into the soil.

The University of Arkansas developed most of the new productive cultivars and most are well-suited to our area. They all are named after Native American tribes and are either thorned or thornless, and they grow upright. There are other varieties of blackberries with trailing habits, which means they need trellises for support.

Blackberries usually have two types of canes. The ones produced the first year are called primocanes. Two-year canes are called floricanes.

Primocanes rise from roots and grow to full height the first year. They do not blossom or have fruit. Primocanes turn into floricanes the following year. These canes bear fruit and die. This means that normally, you must grow blackberries for two years before getting any fruit, although there are a few new varieties that produce fruit on the primocanes in the first year. This also means that the floricanes need to be pruned out at the end of the fruiting season.

Blackberries are planted as either root cuttings or plants. They may be planted anytime during the dormant season but do best if planted in February and into March. No trellis or support is needed for the erect berry plants, but all will need a thick layer of loose mulch. They all will need fertilizer, usually twice a growing season. There is some additional tip pruning needed for best production, all discussed in the above referenced fact sheet.

After planting, the blackberries will need 1 to 2 inches of water per week by irrigation or rainfall. A drip irrigation is ideal for these plants. There also are some recommended disease and insect sprays recommended for the plants.

Garden tips

·       Several early season vegetables are grown from seeds and planted as sprouts or transplants. Some examples are cabbage, cauliflower, broccoli, head lettuce, onions, tomatoes, peppers and eggplant. Most of these take 5-7 weeks from planting indoors until ready for transplanting into the garden. Onions take a little longer to grow.

·       Of these, cabbage, cauliflower, lettuce and onions sprouts should be set out from mid-February to mid-March. Plant broccoli sprouts in March. Tomatoes, peppers and eggplants need warmth and suggested planting time is mid-April, although many people take a gamble and plant earlier, depending on the weather. Look for seeds at local gardening centers or online now if you plan on growing your own transplants.