Now that the lilacs and other spring flowering shrubs have finished flowering, it's time to prune. Many gardeners delay pruning until later in summer, or even next spring, but that's wrong. Pruning late will remove the flower buds for next year's show. After spring flowering shrubs, such as lilacs, forsythia, rhododendrons, weigela, nineback and bridal wreath spirea have finished blooming, you have about 4- to 6-weeks to prune before flowers form for next year.

These shrubs don't have to be pruned every year unless they're growing too large. Then you have a few options. You can remove some of the new growth down to a height you want. If you don't take off too much new growth, the plants will still flower next year. Doing this pruning yearly is a good way to keep a tall and wide growing shrub, such as lilac, from getting too large. Of course, if planted in a yard or location where it can grow to its maximum size, your shrubs will be magnificent when in flower.

The other method is to severely prune the shrub to reduce the size and lower where the flowers are forming. This drastic cutting, sometimes to only a few feet tall, will result in no flowers for a few years until the shrub recovers, but will create a smaller, more manageable plant. Another way of approaching a tall lilac, for example, is to prune one third of the stems each year for 3 years. This will stimulate new shoots or suckers to grow that will eventually flower while reducing the height and still getting some flowers each year.