I need some information on trimming back my common lilac. I have let it get away from me, and I need to prune it back, without doing too much harm to the shrub. Any information concerning cutting back common lilacs during the winter would be greatly appreciated.

When your lilac finishes blooming, prune the spent flowers back to the point just above where the new buds are forming. Dead or damaged stems should be cut off, and a few of the oldest stems should be cut back to the ground. Heavy pruning will result in the loss much of next years bloom, because next years flowers are formed on the plant this year. Don't get carried away when you are pruning.