Blackberries are very sweet and make excellent companions for ice cream, muffins, quick breads, and pancakes. However, there are several different types of blackberries. They fit in the following broad categories:
- Trailing blackberries produce first year canes from the crown of the blackberry bush, not the roots.These blackberries bear on second year canes and will produce lots of sweet tasting blackberries. These blackberries are not hardy in the northern part of the US.
- Erect blackberries have arching canes that are somewhat self-supporting.These plants are much easier to handle when trained to grow on a trellis.Erect blackberries can become a pest because they sprout new canes from the roots.These suckers should be removed during pruning.Summer prune the first year canes so that they will branch and produce more berries the next year.
- Erect blackberries with rather large seeds.These must be trained to a trellis as they cannot stand on their own
- Primocane fruiting cultivars of erect blackberries are easy to care for.These blackberries need to be cut to the ground in the early winter.
- Semi-erect thornless blackberries should be pruned in the summer.They should also be trained to grow on a trellis.These blackberries produce more fruit than either erect or trailing blackberries.
Blackberries are all self-fertile. This means you do not have to worry about getting a female blackberry and a male blackberry. Wild blackberries may carry viruses that will infect your blackberries, so clear the wild ones away before planting your expensive store-bought vines.
Blackberries need good fertile ground that is well drained to thrive. Till your soil to a depth of twelve inches. Place three inches of compost on the soil and till that in good. Go ahead and construct your trellis for each vine. Now you are ready to plant your vines.
Plant semi-erect cultivars five to six feet apart. Plant erect cultivars three feet apart. Plant training varieties five to eight feet apart. Space rows eight feet apart. You will need to plant the blackberry bushes so that they are about one inch deeper than they were grown in the nursery. You can plant blackberries in late fall in warmer regions of the country. However, in cold regions blackberries should be planted in the early spring. Avoid planting blackberries where any nightshade family members - tomatoes, potatoes, eggplants, peppers - grew in the last 2 years, as they can transmit verticillium wilt to blackberry plants.
For trailing blackberries, build a trellis with the top wire at a height of five or six feet. Go down eighteen inches and string another wire. Train the blackberries to grow on the wires by wrapping the canes in a spiral around the wires. After these blackberries have berries, let the old canes turn brown and shrivel. Then cut them off at ground level and start training the new canes on the wires.
Erect blackberries produce stiff, shorter canes that come from the crown and root suckering. These form a hedgerow. A T-trellis is the best thing to grow these vines on. This type of blackberry requires summer pruning. Remove the top one to two inches of the canes when they are four feet tall. This encourages branching and the production of more berries. You will have to continually prune the canes as they exceed four feet. Remove the suckers that are beyond the hedgerow. In the winter, remove the dead floricanes from the hedgerow. You will also need to shorten the lateral branches to about eighteen to thirty inches.
If you have planted primocane-fruiting erect blackberries, cut all canes off just above the ground for the best fruit. In the summer when the primocanes are forty-two inches tall, remove the top six inches. This forces the primocanes to branch and increases the number of blackberries you will get in the spring.
If you planted semi-erect blackberries, the best way to grow them is to train them to a Double T Trellis. You should put a six foot post every place you want a blackberry bush. Take a two by four that is four feet long and nail it, centered, on the post. Install a three-foot cross arm about two to three feet below the top line. String high tensile wire down the rows, connecting to the cross arms.
This type of blackberry needs to be pruned in the summer. When the primocanes are five feet tall, remove the top two inches to encourage branching. In the winter, remove the dead floricanes. Spread the primocanes out along the trellis. Canes do not need to be shortened.
Blackberry vines do not compete well with weeds. Keep them weeded and then mulch the plants to keep weeds down and moisture in. Water one inch a week.
The roots may send up an abundant amount of shoots. Prune them off so the primary canes can produce a large amount of berries.
Blackberries are prone to several pests and problems. Among the most common pests are raspberry borers and fruit worms. The most common diseases are gray mold and viruses. If your plant is suffering from the blackberry disease known as Raspberry Bushy Dwarf virus, the leaves will be have some bright yellow on them, and the leaves of the fruiting vanes may have a bleached look in the summer. The disease known as Blackberry Calico will cause faint yellow blotches on the leaves of the plant.
Blackberries will slowly ripen over a period of two to three weeks. They should be picked every two days. They will last in the refrigerator a few days, but quickly become over ripe and get a fungus on them, rendering them inedible. However, blackberries can be canned or frozen to keep them if you need to. To freeze them, wash carefully and drain in a sieve. Place the berries on a cookie sheet. Place the cookie sheet in the freezer for an hour. Now place the blackberries in a zip lock bag and keep them in the freezer until needed.