I'm not sure it's the location. I have an orchard of 12 apple trees, 3 groups of 4 that I planned to have fruit on different days, thus providing 12 edible apples a day less any golden apples. When I planted the first four, I got one tree that was huge and three little ones. The huge one had flowers by the end of the day while the other three didn't flower until they were big, 24 hours later. It was a bit of a pain replacing that one tree until I had all four in sync, but I did.

So I think it's that the apple trees from the store are in different stages of development when you buy them.