My Doyles blackberry canes from last year were damaged by frost. I trimmed most of them off, now the new canes from this year are fruiting. Will they fruit again next year, or should I trim them off after fruiting like I would a 2nd year cane?
Lenawee County Michigan
It is pretty unusual for erect blackberries to fruit on first year canes (primocanes). Normally blackberries fruit on second year canes (floricanes) which then die and are removed. I expect that these primocanes will fruit next year if they like red (everbearing or fall bearing) raspberries, which fruit at the tips of the primocanes and then the next year fruit below.
Try to prune them as you normally would to promote branching and fruit production next year. Here is a link to erect blackberry pruning. https://ask.extension.org/questions/151224#.Va5Fs7VBnRs