Although the harvest season is months away, it's time to consider some of the small fruits you might grow, especially as nurseries will have their best selection of plants in the next few weeks.
The small fruits include grapes, brambles (raspberries and blackberries), strawberries and several other kinds. Small fruits grow on vines, canes and shrubby branches but not trees.
This week's topic is blackberries. They are members of the Rubus genus, but they are extremely variable, because they cross freely with other blackberries and raspberries.
I am often asked if blackberries grow well in Utah. The answer is that it depends on which blackberries you plant. Part of the problem is that there are many types, including the erect and nearly erect types from the eastern United States, the Eastern trailing types, the Southeastern trailing types, the Pacific Coast trailing types and the semitrailing evergreen types.
All of these different parents have crossed and recrossed to produce the many cultivars we have today.
Their common trait is the large, sweet, dark-colored berries. But don't confuse blackberries with black raspberries. Raspberries will separate from the flower part that holds the berry, but blackberries don't.
We love the fruit, but the canes bring fear and suffering. Blackberries are known for their vicious thorns, which is why many do not like to grow the crop. However, there are thornless cultivars.
All blackberry shoots arise from the roots and basal buds. Like raspberries, the roots of blackberries are perennial while the canes are biennial. The canes grow vegetatively the first year and bear fruit the next year and then die. Each year the plant sends up new canes to replace the dead ones.
Blackberries need room. Set plants 3 feet apart in rows at least 8 feet apart. Erect varieties need no trellising, while trailing varieties need trellising for best yields. As the primocanes grow the first year, thin them to 10 inches apart in the row during the dormant season.
During the summer, head the canes back to 48 inches and let the laterals grow. After they are growing well, cut the laterals to 18 inches. This forces secondary laterals that increase the berry production.
Although the thorns make pruning painful, it is straightforward. Remove the canes that bear each year and let new canes take their place. In some, canes do not die once they have borne fruit. Instead, they send out new growth from the terminal buds on the old canes and continue to grow. When this happens, they become invasive. If canes continue to grow instead of dying, cut them back to lateral branches or remove them completely.
It is important to select blackberry varieties that grow in our area. The thornless are the most popular, but they are generally less hardy. Consider these cultivars:
Arapaho — late season (later than Navaho); erect plants, hardy
Black Satin — late season; large fruit, not as cold-hardy
Chester — late season; hardy, very productive
Dirksen — late season; large, firm fruit
Hull — mid- to late season; large, firm berries, sweet and moderately hardy
Navaho — late season; erect plants, good flavor and quality
Cherokee — early season; erect plants, medium size, good quality fruit
Cheyenne — early to mid-season; erect plants, large, quality fruit
Darrow — hardy, vigorous plants with large thorns; large, excellent quality fruit
Illini — hardy erect plants, good quality fruit
Boysenberry, Loganberry and Youngberry are blackberry crosses that grow in Utah but will do better with extra winter protection.