Blackberries

What plant can be used as a hedge and impermeable barrier all year long, yet produces showy blooms in April and fruit in May? What plant is practically immune to the problems of insects and disease, yet produces one of the best jelly, jam, juice, pie, cobbler and wine fruits known to man? The only fruit which can boast all of these attributes is a berry which is black—commonly referred to as the blackberry.

As a boy hunting in the woods of Tennessee, I never thought that I would someday praise those thorny culprits that tore my clothes, ripped my flesh and taught me to curse proficiently. But the blackberry is probably the easiest to culture, most productive, most versatile fruit in existence. These claims are easily substantiated when one considers the vim and vigor of wild plants that receive no culture.

Originally, when North America was settled, there were only a few distinct species of blackberries, and since the land was heavily forested, they were not abundant. As forests were cut and cleared for pasture and meadow, blackberries spread and there were opportunities for seedlings of different species to grow side by side.

This allowed bees and other insects to cross-pollinate the plants. Thus, man actually started a vast blackberry-breeding project. For the last 150 years, man has been cashing in on this project by selecting the best of the wild hybrids and trying them under cultivation.

In 1959, plant breeders at Texas A&M released the most productive, most adaptive blackberry variety ever grown in the southwest. The Brazos blackberry variety resulted from a cross of high quality blackberries with dewberries and raspberries. Ironically, Texas A&M plant breeders improved upon the perfection of the Brazos by using it as a parent to produce three newer varieties--Rosborough, Brison, and Womack. These varieties have the many favorable assets of their Brazos parent, yet are firmer and less tart. The Rosborough seems to be the most adapted, highest quality improvement. But then Arkansas breeders entered the contest to beat Brazos and now REALLY GOOD THINGS HAVE HAPPENED. The Kiowa blackberry is, to date, the most significant improvement over Brazos. I never thought I would say it but Kiowa is BETTER than Brazos. Another thorny blackberry which is comparable is another Arkansas variety named ‘Chickasaw’. The best thorny varieties in order of preference are Kiowa, Brazos, Rosborough and Chickasaw.

The vicious thorns have always hindered the city folks from want to try blackberries. There are some thornless varieties but until recently they have been of poor quality. Two great thornless varieties out of the Arkansas program include Apache and Arapaho. Apache is the best overall but both would be acceptable.

Most fruit require thinning to insure a large, quality product. Most multi-harvest fruits and berries, such as strawberries, tend to produce the best fruit first. Not the blackberry. Usually the fruit are the same from the beginning to the end if adequate watering is maintained.

The four recommended vanities are blackberries and not dewberries. There is a difference! While blackberries have been divided into hundreds of species, two major types occur. These are the upright growing forms and the prostrate, or trailing, forms often called dewberries. How this name originated is uncertain. Perhaps it was because the berries frequently were covered with dew when gathered.

The upright berries not only have stiff, erect canes, but they also are very thorny. They propagate by suckers or sprouts from the roots. In contrast, the trailing blackberries of America have slender canes, that strike root and establish new plants if they come in contact with the soil,. In general, the upright forms such as the Brazos have a strong flavor, with a somewhat tart after taste. The flavor of the trailing forms are usually milder.

Other types of high quality trailing types of blackberries have been widely grown. These include the Youngberry (a Louisiana berry which is sweeter but not as productive as other varieties), the Loganberry (the oldest of the trailing blackberry varieties for the Pacific Coast) and the thornless Boysenberry (a vigorous variety which produces a large, long, dark reddish black berry and has been shown to be productive in this area. Plants must be trellised.).

What about raspberries? Blackberries are distinguished from raspberries in that when raspberries are harvested, the fruit has a hollow center caused by removal from the stem core, while blackberries do not. Unfortunately, raspberries are not well adapted to South Texas growing conditions. They are extremely susceptible to iron chlorosis (yellowing of foliage) and will not tolerate the hot air and soil temperatures of Texas summers. A fungus disease named anthracnose will also destroy plantings. For these reasons, raspberries should not be planted if an abundant crop is expected. If you just have to try one, get the Dorman Red variety. It may not be the best tasting raspberry, but it will live a day or two! Mulching during the summer helps.

If blackberries are such a productive, easy-to-grow berry, why doesn't every gardener have some? First of all, many gardeners may not have a location that receives sunlight for at least 10 hours each day. Shade limits the productiveness of the otherwise magnificent blackberries.

Secondly, most gardeners allow the rampant growth of their vigorous blackberries to become weed-like rather than productively controlled. Blackberry fruit is produced by one-year-old canes. After the one-year-old canes have produced a crop, they decline in vigor or die, and should be removed after all berries have been harvested in June. Even as blackberries are ripening this year's crop, it's time to prune them for next year. The berries that ripened earlier this year are borne on one-year-old canes referred to as "floricanes". "Prima-canes" –the canes that will be next year's fruiting floricanes –emerged from the ground earlier this spring and in many cases are now five or six feet long. These new canes are readily distinguishable since they have no berries on them and they have larger leaves than the present fruiting canes.

The prima-canes in erect blackberry varieties are very erect and not branched. Top them now at three to four feet above the ground to force them to branch and develop a hedge shape. Left unpruned, the prima-canes will become somewhat unmanageable. Cutting back the primocanes now will also temporarily remove one of the thorny hazards confronted while trying to harvest this year's crop.

One or two more prunings will be needed this summer on vigorously growing blackberry prima-canes. The ideal goal is to have a much-branched, rounded, or box-shaped hedge no more than four and a half feet tall and three feet wide by October.

Blackberry hedge-rows that have become too tall need to be shortened after harvest is completed. One way to do this is to cut all the canes back to two or three feet high with pruning shears, a hedge trimmer, etc. An alternate, more severe after-harvest pruning scheme is to simply mow all the canes to the ground. This requires a tractor and shredder and is a method commonly used by commercial berry growers to rid themselves of dead flori-canes. Growers who install trellis wires in erect blackberries limit their pruning options.

Irrigation and good weed control are necessary to produce sufficient re-growth for a good crop the next year if after-harvest mowing is done.

Trailing blackberry varieties such as Boysenberry or Thornless Boysenberry and Dorman Red raspberry produce new prima-canes that trail on the ground. Leave these canes on the ground at least until after berries on the fruiting canes are harvested. Then the old fruiting canes can be cut off and replaced on the trellis with the new prima-canes.

With proper spring and summer pruning, blackberries will be more manageable and more productive and little or no winter pruning will be necessary.

Blackberries are truly a Southern crop. They are adapted and productive. Kiowa, Brazos and Rosborough are the champions of these brambles. If you have an area that would be suitable for a bramble hedge, transplant plants or root cuttings three feet apart in rows now to insure an abundant production of luscious berries next year.

For more information about growing blackberries, see:

http://aggie-horticulture.tamu.edu/extension/fruit/blackberries/blackberries.html