I am in 5b and winterize my BB in garage.

Your Blueberry plants need to have a temperature of under 45 degrees in the winter to satisfy the recommended chill hours.Probably between 32 and 45 is ideal. Brady

I live in North Central Ohio. Generally it's considered zone 5. (Some of the newer maps say a little warmer). I've grown blueberries in containers for 3 years. None of those winters have been extreme. For winter, I pull the containers together so that I can create one large mound of leaves around & over the containers. I pile the leaf pile a couple of inches above the containers. So far, no problems. My earliest variety was damaged by frost this year, but I think that would have happened if they were in the ground.

I also have a few fruit trees in containers that survive in the same leaf pile.

Please remember 1) some varieties are hardier than others. The rule of thumb I read is that the plants should be rated two zones lower than your area to leave them outside in pots. 2) Our winters have been mild during this period. Maybe a more extreme winter would kill them. If I had the space, I'd still put them in the garage. But if not, go for it.

For me, a novice at gardening, my blueberries have been fairly effortless. Birds, however, are a problem.

I overwintered mine in the garage last year. It worked ok, but due to the warm winter they woke up very early, and I was moving them outside and inside A LOT in the spring. Also one of them overset fruit, meaning all fruit and no leaves.....not sure if it was due to the warm winter or not. In a perfect world I would overwinter them outside and set the containers in the ground, and mulch them. Not exactly sure what I'll do this year. I do know that my 2 SHB's will be in the garage though.

Sorry, something I forgot. If you do bring them in the garage, do not allow them to dry out. They'll still need some water. One guy on the container forum recommends occasionally piling snow on top of the containers. Sort of self-regulates watering according to your plants' needs. The warmer it is, the more water your plants need and the more water that melts out of the snow. Just remember that a 5 gallon bucket of snow only melts down to a few inches of water in the bucket.

I have about 15 high bush blueberries in 10 gallon pots in their 3rd leaf. Once the leaves drop I group all the pots together on the North/Northeast side of my house. I place them next to my foundation on a cement slab. I then mulch the pile with salt marsh hay generously. I also have about 20 high bush blueberry plants in the ground in various spots around the landscape.

The idea is keep the pots out of the wind and sun during the winter time.