Prune spring-blooming shrubs right after they flower.

Right after they finish flowering. That’s the only safe time for lilacs, azaleas, forsythia, and the like. They set next year’s flower buds on old wood over the summer. Prune in fall or spring and you’re slicing off next year’s show.

Signs it needs doing: the bush looks like a tangled mess, blooms are smaller or fewer than they used to be, dead or crossing branches are obvious, or it’s just gotten too big for the spot. Don’t wait for it to look perfect—if you can see problems, it’s time.

Cut out the oldest, thickest stems at ground level to open up the middle. Shape the rest. Go a little harder than you think you should; lilacs especially get woody and lazy without a good chop every few years.

Don’t be shy about it. They’ll thank you next spring.