Features Production Research
Extending the raspberry season with a new fall cultivar

Black raspberries, the first
bramble crop of the summer season, are a favourite among North American
consumers.  Research efforts are currently underway to extend the
season so that black raspberries can continue to be enjoyed in the
fall.

Black raspberries, the first bramble crop of the summer season, are a favourite among North American consumers.  Research efforts are currently underway to extend the season so that black raspberries can continue to be enjoyed in the fall.

Ohio State University (OSU) horticulturists with the South Centers at Piketon are evaluating a new primocane-bearing black raspberry cultivar for production performance, berry size, disease resistance and winter hardiness.

Raspberry varieties produce fruit on the two-year old canes. Primocane cultivars produce fruit in the first season of cane growth, typically from late summer until the first frost or until all potential fruiting sites have flowered.

Shawn Wright, an OSU horticulturist and research associate with the Ohio Agricultural Research and Development Center, says that primocane-bearing cultivars provide a variety of benefits for both the grower and the consumer.

“Extending the season means higher yields for growers and an extended enjoyment of the fruit for consumers, especially for those who support local pick-your-own establishments,” says Wright. “Fall-bearing cultivars are typically more winter hardy since no canes are left that could suffer winter damage, but the low maintenance involved with primocane-bearing cultivars is probably the biggest production advantage.”

Traditionally, black raspberries are high maintenance plants that require tedious hand pruning. Pruning is needed to remove the canes that have produced fruit, or that are winter-damaged or weak. With primocane-bearing varieties, plants are mowed right to the ground in the late winter, eliminating 90 per cent to 95 per cent of the pruning labour.  Cut canes still need to be removed from the field, however, to decrease chances of diseases over wintering, but much less fungicide is used.

Wright and horticulturists in other states are evaluating the new primocane-bearing black raspberry variety Explorer, a product of many years of research based on the breeding and selection work of fruit hobbyist, Peter Tallman, an Colorado resident.

Candace Pollock is a writer with Ohio State University. She can be reached at pollock.58@ag.osu.edu or by calling 614-292-3799.