Q.How Do I Get My Blackberry Bush Ready For Winter?
I just planted a blackberry bush this summer. It hasn’t produced any fruit yet and is still pretty small. What do I need to do to get it through the winter?

Certified GKH Gardening Expert
Unfortunately, summer is quite late in the year to plant blackberries. It may be that it was stunted from late planting. As long as you know that you have a cultivar that will survive your zone, then there isn't much that you have to do for preparation, except for pruning. This will be determined by which kind of fruiting habit your blackberry exhibits.
As far as fruiting- This could be for a couple of reasons. Most, likely, due to late planting. Next would be knowing whether it fruits on this year's growth or next year's growth, but most fruit on older, 2nd year canes.
https://www.gardeningknowhow.com/edible/fruits/blackberries/blackberry-bushes-in-winter.htm
https://www.gardeningknowhow.com/edible/fruits/blackberries/blackberry-pruning.htm