How To Train And Prune Blackberry Bushes And Plants

The method you use to train and prune plants will depend on the type of blackberry plant. Essentially, there are two types of blackberry: 

Erect - Erect blackberry have stiff canes that are upright and arching. They can be grown with or without a trellis as a hedge or shrub border. 

Trailing - Trailing blackberry have flexible canes that must be tied to a trellis or maybe a fence. 

All blackberry plants produce what are called "primocanes." which eventually become "floricanes." Additionally, there are new hybrids, called "primocane-fruiting" blackberry, that require a different pruning method. Scroll down to find pruning instructions for these hybrids.

Pruning Terms:

Learning to master the art and science of pruning blackberry plants takes a little time and practice. It helps to familiarize yourself with a few terms before reading pruning instructions.

Primocane:  These are the green shoots that emerge ever year that mature into a woody-textured cane by late fall.

Floricane:  This is the flowering cane that will produce fruit and which was a primocane in the previous growing season.

Cane:  The main, erect growing shoots (trunks).

Lateral Shoot:  The leafy green growth that develops from lateral buds along the cane, Lateral shoots grow rapidly when the main cane is tipped.

Node:  The thickened portion of a cane where the leaf is attached and a bud is located.

How To Prune Blackberry Bushes

Blackberries produce main upright branches that are called "canes." New shoots will emerge every year that are called "primocanes." These primocanes then mature into "floricanes" in the fall which will flower and produce fruit the following season. Once the fruit has been harvested, the floricanes will eventually die. All spent floricanes should be removed from the plant. By removing the spent floricanes you'll be providing more space for new primocanes to grow the following year.

First Year Pruning

Erect primocanes can be left unpruned during the first year.

After First Year Pruning

Take time to observe the plant and determine what canes need to be pruned. 

During the growing season, usually in June or July, use your fingertips to tip back each developing, new primocane to 48 inches. By tipping back the ends of the canes it releases growth hormones, which stimulates new growth from the lateral buds along the cane. Increasing the amount of lateral canes (branches) will increase the number of flowers and the quantity of fruit produced.

With more aggressive varieties, tip lateral shoots back in the early spring of the following year to help restrict excessive growth.

Do not prune the floricanes before the fruiting season unless they are damaged or diseased.

When the fruiting season is over, use lopper pruners to cut out spent floricanes at their base. Remove all pruned material from around the plants and discard.

When is the best time to prune primocane-fruiting erect blackberries?

There are a few new hybrid blackberries (Prime Jim, Prime Jan) that actually produce fruit on primocanes (new shoots/canes) in fall that grew during the summer. This is different than standard erect blackberries that only produce fruit on primocanes in the following year. Regarding the primocane-fruiting varieties, once fruiting is completed and frost has occurred, all primocanes can be pruned or mowed off. Or you can wait until late winter or early spring and prune all the canes before new growth begins to emerge.

Are there different pruning methods for thorny and thornless blackberry varieties?

Both types are general pruned using the same method. It's just that the thorny canes are more difficult to handle. It's a good idea to wear long "rose-pruning" gloves and a thick, long-sleeved shirt when pruning thorny varieties. On the other hand, thornless varieties have smooth canes and are easier to prune. Thorny varieties tend to produce more canes and more vegetation than do thornless varieties.

Trellising Blackberry Bushes

Erect or semi-erect blackberry plants do not usually need a trellis for support. That being said, heavy crops of berries can weigh canes down. A trellis or fence can be an extra-added measure of support. If needed, you can install a simple one-wire trellis system to help support plants.

Sink two 8-foot pressure treated 4x4 posts about 3 feet deep in the ground at anywhere from 10 to 20 feet apart. In sandy soil you'll need to add a quick-setting mortar mix to anchor the posts. In more dense soils just tamp the dirt down around the post. Make a mark on each post at 4 feet above the ground. Using staples or u-nails, attach 9-gauge coated wire at the posts where marked. Before attaching, wrap the wire one or two times around the post. Make wire as tight as possible.

Harvesting & Storing Blackberries

Harvesting blackberries is fairly straightforward and simple.

When To Harvest Blackberries

The berries are ripe and at peak flavor when they begin to lose their glossy shine and turn slightly dull. A ripe blackberry is deep black with a plump, full feel. If the berry is red or purple, it's not ripe yet. Select plump, firm, fully ripe blackberries as unripe berries will not ripen once picked.

How To Pick Blackberries

There are two types of blackberries to know about: thorny and thornless. Obviously, the thornless are easier to pick. The berry can be pulled free from the plant with only a slight tug. Repeat these operations using both hands until each holds 3 or 4 berries. With the thorny plants, you want to reach into the plant in the gaps, so you don't need to touch anything but the berry you're after, avoiding the thorns.

Note:  Even though blackberries are tougher than some other small fruits, don't overfill your container or try to pack the berries down.

Storing Fresh-picked Blackberries

Avoid placing the picked berries in the sunlight any longer than necessary. It is better to put them in a shady spot. You'll want to cool them as soon as possible after picking. Blackberries can be kept fresh in the refrigerator for up to a week, depending upon the initial quality of the berry. After a few days in storage, however, the fruit loses its bright color and fresh flavor and tends to shrivel. That being said, you can easily freeze berries that you can not use right away - just wash, cut the hulls off and pop them into a ziplock bag, removing as much air as possible. The berries will keep for many months frozen without air.

Plant Long & Prosper!™

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