The forsythia bush grabs your hat every time you walk to the mailbox. The lilacs bushes are so tall and scraggly that you can barely see the blooms. The spirea is blocking the living room windows. The shrubs have taken over your yard!
Shrubs are an asset in any garden, especially when they are allowed to grow in their natural form. Their color and scent turn a barren yard into a garden of delights when they’re in bloom. Their leaves make a wonderful background for annuals and perennials, and bushes give shape and substance to the space all year long. When planted along the property line, they make a wonderful informal hedge. But when they are overgrown and causing problems, it’s time to prune.
Bushes are multi-stemmed woody plants – that is, they grow with many branches coming out of the ground in a group. In an old bush, there are likely to be many, many stems growing very close together, making an impenetrable – and intimidating – mess. Often, some of the branches are dead or dying.
You’ll be tempted to lop off the ends of the branches that are in your way and let it go. That’s a bad choice. You’ll end up with an ugly, badly-shaped shrub. Always prune shrubs at ground level.
First, take out any branches that are dead or damaged. Old bushes often have a lot of dead wood, and cutting that out may be enough to make the shrub beautiful again.
To reduce the overall size of the shrub even more, take out the oldest and tallest branches, cutting them off right at the ground. Cut from the center of the shrub first. Not only are the center branches usually the oldest ones, but cutting some of them out will let light and air into the bush, which encourages better flowering.
Step back and review your work. If you’ve done this right, the bush still has its natural beautiful shape, but it is now smaller and shorter. You might want to take even more branches out, but don’t remove more than one-third of the branches in one year. Pruning more heavily can stress the shrub and make it susceptible to disease and parasites.
When is the best time to prune shrubs? Late winter is always a good time for the shrub’s health, since it will have plenty of stored energy to heal the cuts and create new growth. However, most people want to enjoy the flowers on the shrub, so pruning needs to be timed to avoid interfering with the shrub’s blooming season.
If your shrub flowers in the spring, as lilacs and forsythia do, then the flowers bloom on old wood – wood that the bush grew the previous summer. If you prune these bushes in late winter, you won’t have any flowers to enjoy that spring. It’s better to wait and prune these bushes after they have bloomed. If you want cut flowers for the house, feel free to prune while the bush is in bloom; you won’t hurt anything.
If the bush flowers in the summer or fall, like bluebeard (Caryopteris) or Russian sage (Perovskia atriplicifola), then it blooms on new wood – wood grown in the current season. If you prune these bushes in late winter, you’ll encourage lots of new growth, and lots of flowers.
Go ahead and prune those annoying overgrown shrubs. Do it right, and make them into beautiful assets to your garden.