In the world of botany, a cane can refer to a stalk of bamboo or other grass, a reed, sugar cane, or new growth on a grape vine. Canes are also used to refer to blueberry, currant, rose, and kiwi stems, but we will leave them out for the sake of this discussion, which is more accurately geared toward blackberries and raspberries.
Canes are the long, arching stems of perennial bramble fruits. These canes are filled with spongy pith and normally covered with sharp prickles. Because of those sharp points, bramble canes have traditionally been used in pleaching. Pleaching is method by which living bramble are cut in half, bent over and woven together. As the canes repair themselves, they create a dense, prickly barrier that few thieves or predators would care to cross.
Brambles have perennial roots and crowns that grow new canes each year. New green canes are called primocanes. They turn brown and go dormant over the winter, to one degree or another. In spring, these now 2-year old canes are called floricanes. Flowers and fruit are only produced on floricanes, so you don’t prune them out. Once fruit set has occurred, canes should be allowed to die back before being removed.
Cane growth forms
Raspberry and blackberry canes can grow in one of two forms: erect or trailing. Erect brambles have stiff canes that arch. While not completely self-supporting, erect brambles tend to grow into huge thickets if not pruned. Trailing blackberry cultivars, also known as dewberries, will spread horizontally across the ground. If you live in a cold area, there are even late-season blackberry varieties that can produce late summer crops. The University of California provides an excellent list of blackberry cultivars.
Cane fruit production
Cane fruit production varies between everbearing and summer-bearing varieties. Summer-bearing canes bear one crop in summer on two-year old canes, while everbearing cultivars have two crops, one small crop in summer on new canes and one heavier crop in fall on two-year old canes. Everbearing cultivars are sometimes called fall-bearing. It is a good idea to check with your local Cooperative Extension Office to find the best cultivar for your location.
Brambles can easily be propagated by a method of layering called tip layering. Tip layering consists of digging a small hole, 3 or 4 inches deep, and putting the tip of a cane into the hole and covering it with soil. At first, the tip will grow downward. Then, it will complete a U-turn in the soil and emerge above ground. That bend will develop roots, allowing the new plant to be separated from the parent plant in spring and replanted elsewhere.
New canes should be trimmed to a 6” height. First-year canes can be pruned to a manageable size with renewal pruning, or trained onto a trellis. Stimulate lateral (fruit-bearing) growth by tipping, or cutting off the ends. When working in bramble canes, it is a good idea to wear long sleeves, long pants, and heavy gloves. Those prickles are sharp!
Pests and diseases of canes
Canes are susceptible to a number of different pests and diseases. Bacterial diseases, such as crown gall, viral diseases, such as tomato ringspot, and a slew of fungal diseases, including a number of blights, such as petal blight, spur blight, and cane blight, along with leaf spot, anthracnose, rust, and Verticillium wilt may also appear. If that weren’t bad enough, treehoppers, raspberry cane borers and another type of borer called the rose stem girdler, along with sawflies, lygus bugs, raspberry horntails, vine mealybugs, leafrollers, and tortricid moths (leaf roll) may feed on or damage bramble canes. For all those threats, canes are durable plants, once established. You do need to monitor for environmental conditions, such as dieback, insufficient calcium combined with infrequent irrigation, iron deficiencies, and sunburn damage.
Whichever cane fruit you decide to grow, you will receive many, many years of delicious summer fruits with surprisingly little effort. Just watch out where you plant them, they can spread!
You can grow a surprising amount of food in your own yard. Ask me how!