DManA,
In our Minnesota climate, wait awhile before pruning it back. Our spring is very late this year and it might still leaf out higher up than that. I’d wait a couple more weeks.
Thank. I JUST bought it and planted it. I was doing a little googling and saw one web site that by pruning it back to about 10 inches encourages it to develop the trunk. Does that sound nuts?
Lots of buds swelling up here. My lilacs have a bunch of proto flowers on em. Looks like it’ll be a good year.