How to Prune Summer Flowering Spiraeas

Spiraeas are a large group of pretty flowering shrubs. When you need to prune your spiraea depends on whether the shrub flowers in the spring on older wood (such as Bridal Wreath spiraeas) or in the summer on new growth. If you have a summer-blooming spiraea such as Spiraea japonica or Spiraea x bumalda ("Magic Carpet," "Anthony Waterer," "Gold Flame") you will only need to do a little bit of annual pruning to encourage your shrub to produce loads of blooms. Read on for ways to prune Summer Spiraeas.

Instructions

Difficulty: Easy

Things You’ll Need:

• Bypass pruners (for pruning twiggy growth and deadheading)
• Bypass loppers (for pruning larger branches)

1. Deadhead the blossoms as they fade to encourage a second flush of blooms. To deadhead, simply use bypass pruners to snip the flowers off, making the cut right above a set of leaves. Summer-blooming spiraeas flower profusely for a long period during summer.
2. Do a small amount of maintenance pruning in late winter. Prune just as new buds begin to form. Start by removing any dead or diseased wood or split branches. Prune them back either to the ground or to a spot where they join a healthy, live branch.
3. Take a good look at your shrub. Thin out spindly, crowded or inward-growing branches by cutting them down to a healthy outward-facing bud. Prune two or three of the shrub’s oldest branches down to the ground. As you prune, do your best to create a shrub with a balanced form and graceful shape.
4. If your summer flowering spiraea has bloomed less vigorously over the past couple of summers, you can give the plant a more extensive trim by cutting down all of the branches to 6 inches in late winter instead of doing selective maintenance pruning. This practice encourages the shrub to send up vigorous new growth in spring.