So happy to see all the responses here!
My tree (I originally had two of them, but one died the first winter that it was in its permanent location (I had overwintered them, with protection, in the garden the first year) is planted in full sun -- but "full sun" in the UP is probably like saying "total shade" in Florida and Texas...
Does anyone have any suggestions for what I might do to help protect the tree over the winter for a few years, at least, to kind of get it going? Maybe a heavy mulch around the base? Wrap it with burlap (which would still be relatively practical, since it's only 4-5 feet tall) ? Something else? I am
feeling a bit better, knowing that they leaf out later than other trees for other people as well... and I realize this poor thing is probably rather marginal where I am, but I really do love these trees so I hope it survives!