How to Grow Thornless Blackberries
Planting, Care and Pollination
Imagine picking buckets and buckets of blackberries for pies, jams, syrups and fresh for on top of ice cream WITHOUT getting stabbed by thousands of thorns and trying to balance precariously on a ladder lest you fall in to the thorny abyss! Thornless blackberries make me want to shout ‘Honey, start the car!’ every time head into the house with a full bucket of delicious juicy sweet tangy blackberries from my backyard berry patch. Blackberries are juicy, fruity, sweet and tangy and are high in vitamin C and vitamin K.
History
Blackberries and bramble types of berries have been around for thousands of years. Our Thornless blackberry is a relative newcomer with first variety hybridized in 1921 but the flavour was lacking. It was not until the 1990’s and early 2000’s that flavour and vigour were vastly improved and some great tasting cultivars like Triple Crown, Loch Ness and Black Satin arrived on the scene!
Growing
Full sun (at least 6 hours) and deep, fertile, well draining soil is best for your thornless blackberries as they have long tap roots. A support system is also wonderful, similar to raspberries and will keep your berries at eye level, easy to pick and ripen and up off of the ground. An all-purpose berry food applied in early spring and s topdressing of compost in the row will keep your canes healthy and producing tons!!
Pollination
No mixing of varieties is needed and the canes are self fruitful. Many different types of pollinators are attracted to the simple flowers and you will see everything from tiny Hoverflies to Bumble Bees and Porter Wasps visiting the flowers.
Pruning
Thornless blackberries produce their fruit on second year canes. When pruning and training, encourage the new green canes (which will be your next years crop). The canes that produced the current crop you can prune to the ground in the winter. They are easy to tell as they will be the brown and often dead canes. You are constantly rotating and renewing the plants with this type of pruning. In the winter, you can not only remove the spent canes, you can also shorten the new green canes to encourage side branching and to also keep the cane length to a slightly more manageable spread.
Containers
If you have a deep enough pots to satisfy the longer taproots you can grow in a container. Something around the half oak barrel size is great (2 ½ feet wide by about 2 to ½ feet deep). Ensure you are top dressing with compost a couple of times a year and fertilizing in spring. Excellent drainage is essential.