Winter kill on blackberries

Hi all,
I’m in northern Virginia zone 7b. I’ve been growing triple crown blackberries for about 5 years and had varying levels of winter cane damage each year. Even not terribly cold years seem to result in some cane die-back. This year was especially cold and all of the canes died (seems the crowns are ok so I expect to get new growth this year). I’m just wondering 1) if others have this issue and 2) if anyone has recommendations on how to protect them during the winter. My understanding is that blackberries should be a bit more cold hardy than this but perhaps triple crowns don’t have a high cold tolerance. They’re in a raised bed and I did mulch them heavily this year trying to provide some protection. Any ideas you have are welcome. Thanks!

You should be well within the growing zone for these plants, however this last winter was unusual. The timing of the bitter cold weather plays a big part in what happens. I'm in zone 7a and have die back on several different species, from azaleas, fig tree and loropetalum. All of these usually do fine in my garden. I don't have the blackberries, however, I'm not surprised given what my gardens look like. I tried wrapping my fig tree (it's under 5 foot) with burlap and straw and the top still died back. It's a Chicago Hardy so it's sprouting from the root, but I lost the top. Best case is to prune back the dead and let the blackberries sprout back. You might lay the canes down in the late fall and cover with mulch and see if that helps next year.