Rubus: Raspberries & Blackberries
Each year the International Herb Association selects a plant to be featured as the “Herb of the Year”. The 2020 Herb of the Year is Rubus, the genus that includes Raspberries and Blackberries.
There’s nothing like fresh-picked raspberries or blackberries on a summer day, and nothing like enjoying homemade raspberry and blackberry jam or preserves once the picking season is passed. While a bit “prickly”, these berry bushes are easy to grow once you understand the basics of their fruiting and growth habits.
Firstly, all raspberries and blackberries are self-fertile, meaning that you do not need more than one variety in order to get fruit production. Their flowers are insect-pollinated so bees are a big plus in the raspberry patch.
Raspberries and Blackberries are eager colonizers which will send out suckers and create dense impenetrable patches if allowed to do so. It is best to restrict your plants to rows and remove any suckers that extend beyond their designed space.
Many gardeners choose to erect strong supports for their berry rows and tie fruiting stems to those supports.
There are two types of raspberries; June-bearing/Summer-bearing and Ever-bearing/ Fall-bearing. All raspberries benefit from annual pruning but when and how you prune is determined by the type of berries you are growing.
June-bearing / Summer-bearing Raspberries
Rubus ‘Boyne’ & ‘Latham’
These raspberries bloom and produce fruit on two-year-old canes (stems). After fruiting, the two-year-old stems die. First-year stems are called primocanes and will be green in color. Second-year stems, which will produce the fruit, are called floricanes and will be brown in color.
It is easiest to distinguish the fruiting from the non-fruiting canes during the fruit-bearing season, so immediately after harvest is the recommended time to cut the current year’s floricanes to the ground.
Then, in early spring, prune weak and damaged canes to the ground. Leave thicker, healthy canes in place no closer than 5”-6” apart to provide good air circulation and avoid overcrowding. Tip prune remaining canes back by several inches or down to live (green) tissue to keep them from becoming top-heavy. Don’t tip prune too severely as most of the fruit production occurs on the ends of the canes.
Ever-bearing / Fall-bearing Raspberries
While technically these plants produce fruit on both first and second-year stems the best harvest will be obtained by allowing them to fruit only on first-year stems. This simplifies pruning as the best method is to simply cut all canes to the ground in late winter/early spring. This will produce a heavy crop of fruit on first-year stems in Autumn.
Most blackberries, including the ‘Darrow’ variety that we carry, produce fruit on two-year-old stems (floricanes) so the pruning method is the same as for June/Summer bearing raspberries (above).
Check out the International Herb Association’s Herb of the Year list to see past and upcoming herbs.