By Nicky Boyette – Mid-December is the perfect time to take care of tasks you should have done a month ago when it was 20 degrees warmer – such as pruning blackberry canes in the garden… assuming you took on the challenge of managing a blackberry arbor. Blackberries unchecked will take over a hillside, so why try to manage them in a garden space? Perhaps the canes were already growing, and their crowns lined up into the shape of a tuning fork, and the garden was created around them.
Blackberries are native to Arkansas and have adapted to all parts of the state. In fact, blackberries are native to every continent except Australia and Antarctica. There was a variety recently developed for Siberia, and thousands of hectares of land are devoted to it, which would be a lot of Siberian pruning.
The University of Arkansas Division of Agriculture is known the world over for developing blackberry cultivars, both thorny and thornless. Their varieties are named for Native American groups. Oregon leads the United States in blackberry production and Mexico leads the world in blackberry exports. Blackberries seem to thrive best in moist moderate climates like the Pacific Northwest, New Zealand, England and the Mediterranean region.
Earth-based and Wiccan belief systems claim that blackberry leaves can help remove evil spirits from the home and send them back where they came from. Another legend, according to the Witchipedia website, maintains if blackberries were planted near a home, a vampire couldn’t enter because he would obsessively count the berries and forget what he came there for.
For centuries, all blackberry varieties grew the same way. New canes, called primocanes, established themselves for a year. The second year, the canes become floricanes because they flower and bear fruit. All varieties bore fruit the second year.
However, in 2004 the University of Arkansas growers introduced the first commercial primocane-bearing blackberry cultivars, which meant the canes bore fruit the first year. In 2014, the University of Arkansas introduced the first thornless primocane-bearing blackberry variety named Prime-Ark Freedom. Most gardeners will have the traditional varieties that bear the second year, so this pruning yarn is about those varieties.
Prickly
Pruning blackberries is an art, so everyone might do it differently. Some sources suggest an autumn clean-up pruning followed by tip-pruning in spring. Gurney’s Seeds says a good time to prune canes would be late winter because the old, spent floricanes are easy to distinguish from the primocanes. Besides the trailing blackberry varieties most gardeners have, there are erect and semi-erect varieties that require pruning on a different schedule, but the same principles apply.
Nevertheless, the first thing to do when it is time to prune blackberry canes is to put on armor. Then, on the balmy 40° December morning, look for brown, dried-up, dead floricanes and cut them off at the bottom. Getting to the bottom of the cane requires delicate gymnastic maneuvers to avoid the prickly primocanes all around. Thorns on dangling primocanes are meant to grab and poke, so that is what they do. Even an adept pruning master carefully tai chi-ing under and among thorny primocanes might get snagged first on the cap near the left ear which causes a reflex which causes snags on the shoulder and sleeve and pricks on the right glove and left leg.
Other than the rustling of leaves in the woods, the only sounds in the garden are the little yelps of joy as the gardener extricates body parts from prickly entanglement with another hour of pruning left to do. Asparagus is easier.
When it is time to prune the primocanes, look at the ground and see where the canes emerge. Canes will produce better if they are only minimally entangled, so pick the three or four strongest canes within a 12-inch cluster. Prune away any others. Guide the canes into a space of their own on the trellis or fence. This involves loosely tying them to the trellis, and you cannot tie garden twine with gloves on, so you must pull your gloves off at the very time you are handling the canes, which is why you need the gloves. Pruning blackberries is one irony after another.
Once the canes have their own space, trim them back to three or four feet. Laterals off of the main cane should also be pruned back but leave at least five or six buds for each. All pruning should be adapted to the gardener’s space, style and imagination. Leaving a long lateral along the bottom where there are fewer branches might mean more berries, or it might get lost down there when the burst of growth overwhelms the early summer garden.
In the spring, once growth begins, trim the tips off the laterals to encourage more branching because berries grow on the branches. During the summer, new primocane laterals will run rampant onto pathways, so there is always maintenance.
In fact, the blackberry arbor will become the standout representative of summer garden chaos. Once the summer garden explosion begins in June, the gardener realizes the blackberry trellis that looked useful and artsy last winter is gone and will not be see again until time for baseball playoffs. And until that time, there, in the middle of the garden, is a jungly blackberry bramble in the shape of a tuning fork teeming with wonderful berries for a couple months.
Harvesting blackberries is also accompanied by little yelps of joy.
Nicky – Entertaining and informative article on blackberries. Thank you. – G Sims, Benton County Master Gardeners