LEARN HOW TO PRUNE YOUR SHRUBS AND TREES Pruning seems like a no-brainer until you have your shears in hand and are standing in front of your shrub or tree and you aren’t so sure where to start and more importantly, where to end! Here we offer some simple tips for best-pruning practices to help guide you as you stand in front of your beloved plant or to give you some background information when you decide to hire the experts. “It’s key that you don’t treat your entire property in one way when it comes to pruning. It’s important to know what you have so you know what to do and when. Many of our clients ask us to prune during their fall clean-up, which isn’t ideal because in the fall you can only work on a few of the plants in your landscape. Since so many of the plants are off limits, it’s best to wait until the dormant or green season to prune,” says Mike Annes, Greenwise Client Relationship Manager.
Why Do I Need to Prune?Pruning serves so many purposes, from encouraging flowering and fruiting to getting rid of diseased or damaged branches to promoting growth. The key is removing certain kinds of growth before problems start. For example, when you properly prune younger trees, you help the tree develop a robust structure and grow in an eye-catching way. If you start when the tree is young, you are less likely to end up with an overgrown tree that will require a lot of corrective fixes later. Pruning is a good way to cut back fast-growing shoots, suckers, or water sprouts, which don’t look good and are weak, so more likely to break as they grow. What are shoots, suckers, and water sprouts, you ask? Good question. Shoots and sprouts are terms used interchangeably and refer to those new branches that sprout from older branches in the tree or shrub. They often sprout or shoot up perpendicular to the larger branch. You don’t want to get rid of these entirely, only prune about half of them. YOU CAN SEE THE WATER SPROUTS OR SHOOTS GROWING STRAIGHT UP FROM THE MAIN BRANCH Suckers come up from the ground and compete with the existing tree, so you want to get rid of all of them so they won’t weaken the tree. Suckers in bushes, such as Lilacs and Viburnums, will help rejuvenate the plant, so you don’t need to get rid of those; maybe just thin them out, depending on how many there are. SUCKERS FORM AT THE BASE OF A SHRUB OR TREE Obviously pruning diseased, broken, or crossed branches is necessary to prevent large branches from breaking off and causing injury or property damage. Crossed branches can rub against each other, creating wounds that invite infection and boring insects, which can affect the entire tree. Don’t overdo it! We recommend that you don’t remove more than ¼ of a plant each season unless you are pruning to rejuvenate your plant and then it’s okay to prune down to 12 or 18”. By over-pruning, you can create even more stress, which can lead to even more suckers and water sprouts as your tree tries to rebound. Thinning branches help your plants breathe. When air circulates properly through a plant, it helps your plant remain disease free and reduces insect damage. When thinning, you want to thin out those branches that make up the dense mass of the plant. Be careful! Take a step back after every few cuts to make sure you are creating the shape you want. You don’t want to hollow out the center, so be careful not to prune too much.
When Should I Prune?When to prune depends on what you are pruning. Around here, from November to mid-March, our plants are in a dormant stage. Did you know pruning cuts heal faster during dormancy? That makes winter the best time to prune, shape, and thin many of your deciduous plants, trees, and shrubs. Even making large cuts is a low-risk venture this time of year. Plus, you get fantastic results in the spring! Winter is also the only time you should prune Oaks and Elms. Oaks are protected trees in our area and should only be pruned in the winter so that you don’t transmit diseases. Evergreens and Maples should be pruned in the spring, summer, or early fall. Pruning evergreens too late can promote young growth that isn’t strong enough to handle the cold weather, making it burn off and turn brown. And Maples bleed, so you shouldn’t prune them after November. By bleeding we mean you’ll see sap dripping from the cut you’ve made. This won’t impact a mature tree, but it may cause problems for a sapling to lose so much sap. It’s best to avoid any problems by pruning your Maples in the summer. Once the leaf buds open, the sap is no longer under pressure and won’t leak out during pruning. Your flowering shrubs should be pruned as soon as the flowers fade in May or June. If you prune them after July, you might affect how much they flower the next season. Here’s a quick guide for pruning depending on if you are doing aesthetic or structural pruning.
Aesthetic PruningAesthetic or in-season pruning is when you want to reduce the height and width as well as the overall shape of your shrub or tree. Here’s the rule of thumb:
- Prune in season from May through July
- Prune flowering shrubs, such as Lilacs or Viburnum, soon after the flowers fade between May and June
- Prune hedges between May and July, and if you’ve got a formal hedge, you should do this twice during the season