Lilacs... in August?

When David told me that our lilac bush was blooming, I was completely confused. Lilacs in the Northeast bloom from the end of April (where we are in NJ) to the end of May (in Upstate NY), but I'd never heard of them blooming in August! Sure enough, I checked the bush and found a few tiny blossoms! And the best part, they smelled just as wonderful as they did in the spring! I have no idea how our bush managed to bloom twice this year, but it was a great surprise!