Q.what size pot can I grow a burning bush in on my deck?
What size pot can I grow a burning bush in on my deck?
Can it grow in a climate that goes to -30 in the winter?
The size container will depend on the size of plant that you are starting with.
A 2 gallon nursery pot may be potted into a container such as a half whiskey barrel.
You will need to provide some extra winter protection for a potted burning bush. You can wrap it with insulation or move to a sheltered area such as a garage after it has gone dormant.
https://www.gardeningknowhow.com/ornamental/shrubs/burning-bush/burning-bush-care.htm