I'm struggling to find some potted trees. I want some for the front and back doors of my house. I also want to use them in our wedding next year in spring.
I would really like either blue or white flowers on them, and for them to be hardy as they need to be able to survive winters outside. They should flower in spring as well. 
Any advice on what to buy? I've checked I dunno how many websites and can't find anything.