can i cut overgrown lilacs now in Iowa?

Question

15 foot tall with smaller shoots — want to cut large wood out

Answer 1

It is best to cut them right after flowering. Just don't wait too late, when the new flowering buds are developing. This article will help: https://www.gardeningknowhow.com/ornamental/shrubs/lilac/pruning-lilac-bushes-when-to-trim-lilac-bushes.htm