Two North Star pie cherries in my vegetable garden last week. I planted four of these in the spring of 2009. All of them are doing well, but the one on the left is doing scarily well. The only difference is that the one on the left sits at the head of my asparagus bed, and asparagus, which I love, gets favored treatment, including much of my limited store of kitchen compost in early spring.
This spring, I made sure that all my North Stars got a shovelful of compost. But the other three don't yet seem to be catching up to the freakishly healthy tree.