Posts. Hybrids usually have only one stump, and they will likely die from this kind of drastic pruning. I would not have cut below where they branch, but cut the branches cleanly back to the stub, like a good pollard. Question: I have a very large rhododendron (2.5 m × 2.5 m/8 ft × 8 ft) that I would like to cut back severely after it blooms. Rhododendrons are extremely resilient plants, and your rhododendron will survive and grow back, but don’t expect to see much foliage or flowers for a few years. Pruning may be beneficial but probably won’t solve the problem. There are over 800 species of rhododendrons ranging from spreading groundcovers a few inches high to 100 foot tall trees and many thousands of registered, named varieties. Rhododendron before pruning. What do you recommend for this old, tired rhododendron? Stock plants in the arboretum are more tolerant of such pollarding or coppicing than canned stock is. Any revitalizing to be accomplished must be done on new wood, supplied by drastic pruning. If you leave enough of the prior year’s foliage and keep an even shape to your rhododendron, your odds are better that you’ll see some flowering the next year. Prune these back down to a set of leaves (rosette) that are within the plant. Thanks for any suggestions. You can prune young plants and old plants to create a better shape. In fact, the American Rhododendron Society recommends trimming the bush to control its size, if you want to pick the flowers for an arrangement or to remove spent blooms through the season. For the specimen to the left, I would have removed all but a single branch from the four main trunks, or just cut back to where each of the four trunks branch. Leave the outward-facing branches to reduce the rhododendron’s size while maintaining its shape. It is important to remove the flower stems from the shrub once blooming has ceased. Change ), You are commenting using your Google account. ( Log Out /  How to Prune To develop a good structure on young rhododendrons, we tip prune them for their first five years. Change ), You are commenting using your Twitter account. Thus, after 20 years, if they’re never pruned, they’ll measure approximately twice that.). Hopefully you will see some new growth (on the old wood), which is an indicator that your plants will survive pruning without problems. Follow these tips to prune your rhododendrons effectively. Rejuvenation pruning is used to restore old rhododendrons that have become leggy, overgrown, or otherwise just plain ugly. And the great news is, there are no prickles!! However, crepe myrtles are a type of flowering tree rhododendron with long, thick branches. After the plant is ten years old, we would not recommend this type of pruning … Beware that pruning a large rhododendron heavily may cause the plant to stop flowering for one to two years. If the specimen to the right is the same as the specimen to the left, I would have removed it completely. Others that sprout abundantly should not be opened excessively to light. If the wood is old… Copyright Leaf Group Ltd. // Leaf Group Lifestyle. If in doubt, proceed cautiously, or seek expert advice. Of course, in my own garden, where production is not a concern, I can let them take their time. Winter Protection: Don’t Waste Your Time ( Log Out /  They far exceed the dimensions you saw on the label when you bought it and probably used when calculating where to place it. Some that do not sprout readily from old wood cannot be much improved. Prune just above the growth joints using hand-held pruning shears. The best time to shape or prune Rhododendrons is in the spring after they finish blooming. Doing this will improve air circulation in and around the plant. In the future, when your rhododendron approaches the size you want, make a habit of pruning your shrub modestly after it blooms to restrain its development, shortening one branch out of three annually. You can continue this practice and will be rewarded with plants that have increased branching, and thus more flowers. Do any severe pruning in late March, before the rhododendron blooms to encourage healthy re-growth. You've nothing to lose I used to regularly prune any I had as they're like weeds up here. Learn how your comment data is processed. Prune any branches that are growing back into the plant. Some gardeners cut back even more severely, to 15 cm (6 inches) from the ground, but that sometimes backfires, the shock being so brutal that some plants don’t recover. When old rhododendrons become unthrifty in appearance, the cells in the vascular bundles have become hardened or plugged and no longer function normally. This applies to both evergreen and deciduous azalea varieties. You should prune the rhododendron before the buds form so you don’t lop off the following year’s flowers. By pruning away lower growth to expose gnarly inner trunks, rhododendrons make nice small trees, particularly if there are upstairs windows above. The easiest style of pruning is trimming off any dead or dying parts of your rhododendron with pruning shears. If you leave enough of the prior year’s foliage and keep an even shape to your rhododendron, your odds are better that you’ll see some flowering the next year. Rhododendrons are nice shrubs perfectly suited to being grown in pots. Pruning large rhododendrons can seem like an overwhelming undertaking, but it doesn’t need to be. Change ). The new growth that develops will be crowding the walkway from the beginning. Twenty-four species of rhododendron are native to North America. You should prune the rhododendron before the buds form so you don’t lop off the following year’s flowers. Rhododendrons can be pruned easily and very effectively. Answer: Many rhododendrons do turn into garden-grabbing monsters over time, becoming tall, wide and sometimes quite lanky. How Severely Can You Cut Back a Rhododendron? Wrapping them in burlap or geotextile may make you feel useful and does keep the wind off, but won’t keep them any warmer, so is generally a waste of time. Your rhododendron should only need pruning to remove dead or diseased branches, to shape it for neatness, or to revive the growth of an older plant whose flowers are dwindling. You can prune earlier in the spring, but will lose the flowers that would have appeared on the pruned stems. A: Rhododendrons are usually pruned in the spring, right after blooming. The idea that rhododendrons need winter protection to survive in cold climates is highly exaggerated. With Rhododendrons, you can simply snap off the old flower head – but make sure that you do not damage the new bud growth. (Few gardeners seem to know that the dimensions given on a rhododendron label don’t indicate its final size, but rather its dimensions after 10 years of growth. Good thing is rhododendrons are one type of plant that respond well to this drastic form of pruning. It can be done with a snapping action of thumb and finger. In the first year, your shrub will start to regrow, producing new stems and leaves, but will probably appear very spindly and unequal at first. Don’t cut a hybrid rhododendron down to the ground. Don’t use hedge shears. Some are wild. Change ), You are commenting using your Facebook account. Pruning branches after buds are set removes next year's flowers. Dead leaves will look yellow or brown, and dead branches will be crispy and snap easily. "If you want to deadhead them or prune them, grab the old flower spike and twist between your fingers - it comes right off, then they'll send up new shoots. Azalea and Rhododendron Pruning Azalea and Rhododendron Pruning and for or all other evergreen shrubs that flower in late winter, spring, or early summer. Over time, a rhododendron that isn't properly maintained will become … ( Log Out /  It will probably take 2 or even three 3 years before it really fills in and starts to look good again. That way, you can keep it at a more acceptable size even as you enjoy an abundance of flowers each year. Prune your large rhododendron right after it finishes blooming. Some folks just grasp the stem with their thumb and forefinger and snap the truss from the plant. Actually, because they are stock plants that provide cuttings rather than bloom, some get pruned rather aggressively every few years or so, and some even get pollarded or coppiced. Gads! In the late summer, prune after flowering has ended, and before new leaf growth is active. Rhododendrons and azaleas set next year's flower buds by mid to late summer. You can identify the growth joints by looking for the point where the plant started that year’s growth. If you leave enough of the prior year's foliage and keep an even shape to your rhododendron, your odds are better that you'll see some flowering the next year. The most common type of pruning is maintenance pruning, which simply involves the removal of spent flowers and old, dead wood. In the future, when your rhododendron approaches the size you want, make a habit of pruning your shrub modestly after it blooms to restrain its development, shortening one branch out of three annually. This site uses Akismet to reduce spam. Pruning is best done after flowering in late spring, this gives the best possible chance of flowers still coming the following season. This preserves the current seasons bloom, and allows time for the plant to produce flower buds for next years bloom. To prune your rhododendrons, you will need a pair of pruning shears or loppers, depending on the type of rhododendron you are pruning. Scaly-leaved rhododendrons and all azaleas can be pruned to any point on a branch or shoot and new growth will come from buds lower down. Fill in your details below or click an icon to log in: You are commenting using your WordPress.com account. There are several ways you can prune a large rhododendron, depending on how much you need to cut it back. Plan the perfect garden with our interactive tool →, “Rhododendron Basics,” by Harold E. Greer, “Pruning a Large Rhododendron,” by Sandy Feather, "Tips for Beginners: Pruning Large-Leaved Rhododendrons," by Warren Baldsiefen. Most rhododendrons respond well to pruning. There are many rhododendrons adapted to cold climates: hardiness zone 4 and even 3 and yours undoubtedly belongs to that group. I live in hardiness zone 4b. If your large rhododendron is growing out of control and starting to look like a mess, you’ve got some pruning to do. Fortunately, yes, you can cut an overgrown rhododendron back quite severely and thus reduce it to a more acceptable size. Name – Rhododendron Family – Ericaceae Type – shrub Potted height – 26 to 32 inches (0.6 to 0.8 meters) Exposure – part sun and shade Substrate – heath soil Foliage – evergreen Flowering – March to June. However, in our regions, rhododendrons do not always recover from such pruning. Restoring overgrown rhododendrons (Article by Alison Marsden of Gardening by Design - Advice, coaching, design & teaching in West Kent & East Sussex) Evergreen, large leaved Rhododendrons make a fantastic display in May and June but not all of us can let ours grow as large as this superb specimen at Riverhill Himalayan Gardens near Sevenoaks in Kent. Hybrids usually have only one stump, and they will likely die from this kind of drastic pruning. Beware that pruning a large rhododendron heavily may cause the plant to stop flowering for one to two years. Key Potted Rhododendron facts. To remove old flower trusses on rhododendrons, use a pruning shear to snip the truss at its base, about 1/2 inch above the emerging flush of new growth. Photo: Oh Kaye, flickr.com. And it may well not bloom abundantly until the third year either. Pruning a leggy rhododendron. If I were to put the effort into cutting back a rhododendron, I would have left only about five stout canes, and not branched with all those stubs. It is too close to the walkway. You really need to focus on solving the other problems and prune only as a secondary measure purely for cosmetic or sanitation purposes. Some never recover. Overgrown canned stock is not so tolerant. About Rejuvenation Pruning. Perhaps the most common pruning tasks are when you want to rejuvenate an old collection which has become completely overgrown. For example, azaleas can typically be pruned with handheld pruning shears as the wood of azaleas is small and thin. Before doing any cutting, look to see if there are small shoots near the base of the shrub. That way, you can keep it at a more acceptable size even as you enjoy an abundance of flowers each year. When you are ready to remove the old trusses from your rhododendrons, take the sharpest set of pruning secateurs you have and make sure to you sterilise them first to prevent the spread of diseases. When to Prune: Typically, rhododendrons and azaleas are pruned after they bloom. Prune a large rhododendron that is old and has multiple stems coming up from the ground back to its stumps, with no leaves remaining. Honeyheart Posts: 39. The best time to prune rhododendrons is after a full flush of blooms. Pruning Limitations. As long as an old, leggy rhododendron is not weakened by a disease, it tolerates and responds very... Time Frame. Rhododendrons & Deciduous Azaleas (Mollis Types) Pruning Azaleas mollis types (deciduous) and Rhododendrons. Your rhododendron certainly wouldn’t reach such a large size if it weren’t well adapted! ... will it rejuvenate or will I kill it? It is not pretty, but it works for what we need them for. So, in winter, just let it fend for itself. Step 1: When to Prune. Look for any branches that are growing inward. The most basic form of pruning - often sufficient, is simply to dead-head the old flowers - before they are allowed to make seed - by cutting back to first set of buds. Cut an overgrown rhododendron back quite severely and thus more flowers easiest type of pruning a. Cutting, look to see if there are many rhododendrons adapted to cold climates hardiness... You do n't like and decide pruning old rhododendrons cutting it back identify the joints. Focus on solving the other problems and prune only as a secondary measure purely for cosmetic or purposes! 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