Gordon Johnson, Extension Vegetable & Fruit Specialist; gcjohn@udel.edu
Originally, commercially available blackberries were floricane types, that is, they fruit on last year’s canes. Over the last decade, the University of Arkansas has released a number of primocane blackberries that are commercially viable. Primocane blackberries fruit on current season canes, allowing for blackberry production from mid-summer through frost. In subsequent years they have the potential for two-season fruiting – in early summer on overwintered canes and as a late summer and fall crop on current season primocanes – as much as 6 months of production.
What is exciting about primocane blackberries is that they offer extended production potential into the fall. They also offer flexibility in production as they can be treated as a two-season fruiting crop summer and late summer-fall (overwintered and primocane production) or single season (primocane only) production late summer-fall. Blackberries are generally well adapted to Delmarva conditions but will shut down if temperatures stay in the 90s for extended periods. Primocane blackberries will be flowering and fruiting much of the time in the cooler late summer and fall.
Some recommended Primocane Blackberries for trial on Delmarva:
Thornless
Prime-Ark Horizon
Sweet-Ark Ponca
Sweet-Ark Caddo
Prime-Ark Traveler
Prime-Ark Freedom
Thorny
Prime-Ark 45
Variety descriptions can be found at this site: https://aaes.uada.edu/fruit-breeding/blackberries/
Prime Ark Freedom Blackberry – the original thornless primocane release with large berries well adapted to U-pick in Delaware.