Sometimes they can be slow to get rolling. Try breaking off a tiny bit of a twig and see if there's green.

I planted a dogwood tree a couple of years ago. The first summer it had maybe 12 leaves on it total. I was ready to pull it out. But I left it and it got many more leaves the following year. It even grew some. I'm on year 3 and now it is leafed out and flowering. Just make sure you water it a lot during the summer.