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Trim rhododendron in summer


When is the best time to prune rhododendrons? – The Morning Call

Q: I have two rhododendrons in my front yard that are looking very straggly. When can I prune them and how much without killing them?

— Karen Eppensteiner

A: While it is possible to prune these plants anytime from early spring to mid-summer, the recommended time to prune is immediately after blooming. This is because the plants begin to form next year’s blooms soon after shedding the current year’s flowers.

The buds set in mid- to late-summer, so summer pruning will decrease next year’s bloom count. Late pruning — late summer into fall — not only cuts bloom count but also produces a spurt of tender foliage that may not have time to harden up before the killing frosts of fall.

What you are describing is called rejuvenative pruning. Cut back the branches to just above a viable bud. If the wood is old, the buds may not be viable so unless you want to eliminate the branch, don’t cut back too far.

The best, or at least safest, practice is to trim back in stages over a three-year period. Cutting back only a third of the plant each year ensures that the rhododendron will have enough leaves to produce adequate food for the plant.

With patience, in three years you will have a healthy, full plant.

New Guinea impatiens

Q: I bought 90 New Guinea impatiens, five flats with 18 plants per flat. They are planted in various pots in my yard. All of them get minimal sun and plenty of water.

I have about five plants that just “passed out” (not from lack of water). Other plants in the same pot as the various ones that passed out are fine. Almost like something laid on top of it and wrecked each of these particular plants. Again, others are fine. Each of the five are not about to make a recovery. All my plants did have flowers and buds on them and were very healthy when I purchased them. Any insight would be much appreciated.

— Janice

Q: I have two nice plant that have a problem. They were getting two to three hours morning sun, and doing fine. I noticed heavy drooping on both plants so placed them on patio in shade. Temp here is 95 during day. Now I placed them in water basin and in an hour they were great. Here’s the problem: In two hours in shade they are both drooping. What to do? No sign of mildew bugs, etc.

— Emelie

A: New Guinea impatiens (Impatiens hawkeri) are popular and colorful annuals. They are touted as light tolerant but most do best with four to six hours of sunlight or an eastern exposure with afternoon shade. In hottest weather, they may need additional shade from the sun. Excess sun will cause plants to produce smaller and fewer blooms, and the leaves will show damage.

The soil should be constantly moist but not wet or soggy. Make sure containers have adequate drainage holes, as these plants are susceptible to root rot.

Temperatures should be warm, 70-80 degrees in the daytime and 55-65 degrees at night are ideal. Cool temperatures, below 45 degrees, can be damaging, even fatal.

Keeping the soil moist is important as they are very sensitive to improper watering and will wilt quickly. Fortunately, if there is no underlying root problems, they usually revive if watered soon after wilting.

Fertilize with a single application of slow-release fertilizer or a light feeding with a balanced water-soluble fertilizer every two weeks.

Problems most commonly associated with New Guinea impatiens are root rots (pythium or phytophthora) and stem rot (rhizoctonia). They also get necrotic spot virus and tomato spotted wilt. Both of these problems will appear as black spots and lesions on the stem or stunted or distorted leaves and then a total plant collapse. There are no treatments for these problems.

In Janice’s case, minimal sun and plenty of water may be the problem. These are not shade plants; they are recommended for part shade to sun. I would recommend more light and less water. The flattening she describes can be a total plant collapse, which would indicate some sort of rot. I would suggest immediately removing the problem plants and destroying them. If the problem is a wilt, it is possible that other plants in the same container may already be affected. In any case, the pots should be cleaned and any soil replaced.

Emelie’s situation has similar concerns: Two to three hours of sun is really on the low side for these plants, and the quick wilting after reviving sounds like a problem with the roots. She does not mention if she is keeping the soil evenly moist but well drained. In this case, as with Janice, I suspect some form of wilt, which will eventually kill the plants.

However, another problem could be the temperatures. We have had some very cool nighttime temperatures that can damage these plants.

A reader’s take on pear trees

Your comments about the Bradford Pear were very kind in my view. My family lived on Bethlehem’s South Side for 40 years. A few years before we moved there (about 1970) the city planted hundreds of these trees along our narrow streets. They were lovely for a few years but when they matured their huge horizontal branches began to break. Over the years four cars were destroyed by these branches in our immediate neighborhood, and I often wondered when someone would be killed by a falling branch. The upper branches grew into the utility lines and PPL chopped them unmercifully. Eventually the neighborhood looked like a war zone because of the broken Bradford pear trees, or what was left of them.

The city refused to take responsibility for planting trees that were totally inappropriate for the neighborhood, and they insisted it was the homeowner’s responsibility to maintain or remove them. Folks on the South Side generally do not have the means to hire a tree service, so it was left undone. The city eventually put the Bradford pear on its “Do Not Plant” list. A few Cleveland pears followed, but they quickly grew into the power lines and the odor in the spring was terrible.

— Robert Bauer, Bethlehem

Sue Kittek is a freelance garden columnist, writer, and lecturer. Send questions to Garden Keeper at [email protected] or mail: Garden Keeper, The Morning Call, PO Box 1260, Allentown, PA 18105.

This week in the garden

Planting:

Plant a second crop of snap or pole beans, radishes, carrots. Sow small sections of crops like beans, radishes, lettuce, and spinach at regular intervals to create a longer harvest.

Set out tomatoes, basil, eggplant and pepper transplants as weather and soil warms.

Start seed for: Baby’s breath, cosmos, zinnias, salsify, eggplant, summer squash and winter squash.

Direct sow: Corn, okra, and rutabaga.

Continue sowing: Snap, bush and pole beans, cantaloupe, melons, cucumbers, rhubarb, summer and winter squash.

Plant or pot up summer bulbs and tubers such as dahlias, cannas, calla lilies, and caladiums.

Plant bare root trees and shrubs. Make sure the soil is dry enough to work: Don‘t dig or plant in mud.

Buy annuals for containers, annual garden beds and to fill in bare spots in perennial or shrub beds.

Seasonal:

Stalk tall flowers and provide supports for vining plants. Cut back boltonia by half the size of the plant. Cut Joe-pye weed back to three feet tall. Cut back candytuft to encourage bushiness. Shear back woodland phlox (P. divaricata)

Deadhead sea thrift (Armeria), centaurea, centranthus ruber, dianthus, fringed bleeding heart (Dicentra exima), hardy geraniums, bearded irises, red-hot poker (Kniphofia uvaria/tritoma), catmint (Nepeta), herbaceous peonies, oriental poppies, pincushion flowers (Scabiosa).

Fertilize Siberian irises, summer phlox (P. paniculata) and Shasta daisies with a light application of balanced fertilizer

Divide spring blooming perennials after they finish blooming.

Cut back peony flower stems as the blooms fade. Allow the greens to grow until fall, then cut them back to the ground.

Clip back iris flower stems as the blooms fade; divide plants in crowded beds

Pinch back helenium, chrysanthemums and asters to promote bushy growth and more flowers. Continue to pinch back new tips at two-week intervals until early July.

Ease out your plants that wintered over inside. Protect from direct sun for the first few days. Start with an hour or so on a warm day and increase outdoor time until the nights are regularly in the 50 degree range before leaving them out for the season.

Spread spring and summer mulch two to three inches deep and applied a few inches away from foundations, tree trunks and other plants. Fluff mulch and add more if necessary.

Lawn:

Keep newly seeded or sodded lawns watered; supplement rain in weeks where we receive less than an inch.

By mid-June: Apply spring fertilizer treatments.

Apply pre-emergent crabgrass control in the next few weeks.

Fill in holes and low spots in lawn.

Apply corn gluten-based weed control in the garden; reapply at four to six week intervals.

Chores:

Check hoses; replace washers and correct leaky connections.

Dump standing water and remove anything that may collect rainwater to help control mosquito populations.

Provide deer, rabbit and groundhog protection for vulnerable plants. Reapply taste or scent deterrents.

Clean and fill bird feeders and birdbaths regularly. Clean up spilled seed and empty hulls.

Clear gutters and direct rainwater runoff away from house foundations.

Safety:

Don’t prune anything that can’t be reached from the ground. Hire a certified and insured tree pruner for high pruning or heavy branches or for any work around power lines.

Photograph storm damage before clearing or repairing for insurance claims and file promptly.

Avoid tick bites: Use an insect repellent containing Deet on the skin. Apply a permethrin product to clothing. Wear light-colored clothing, long sleeves, hats and long pants when working in the garden.

Stay hydrated. Drink water or other non-caffeinated, nonalcoholic beverages.

Apply sunscreen, wear hats and limit exposure to sun. Wear closed-toe shoes and gloves; use eye protection; and use ear protection when using any loud power tools.

— Sue Kittek

How And When To Prune Rhododendrons

How And When To Prune Rhododendrons

Robert L. Furniss
Portland, OR

"How do I prune my rhododendrons?"  The usual answer to this frequently asked question is, "Very little.  Remove the dead and sickly branches and let the plants grow naturally."  Sometimes this is good advice.  It applies best to small, bushy-type rhododendrons and to rhododendrons in woodland and mass plantings, but it is not the whole story.  At times it is adequate, even misleading.

Definition. Pruning is the removal of parts of a plant to control growth.  More art than science, it is an adaptation of natural processes to achieve horticultural objectives.  Broadly, pruning includes the removal of any unwanted parts of a plant, including flowers, buds, soft wood, hard wood, basal sprouts, and sometimes roots.  Pruning is not a routine treatment applied cookbook style.  Nor is it a substitute for requirements for vigorous growth, such as fertilizing, watering, controlling pests, and planting properly.

Objectives. Pruning is for some cultural purpose.  Before plant surgery, the grower should decide what the pruning is intended to accomplish.  Is the grower trying to revitalize treasured old plants, to produce plants for sale, to stimulate maximum number of highest quality flowers, to enhance the year-around appearance of the plants, or to achieve some special landscape effect?  Has something gone awry that needs correcting?  The kind and amount of pruning depends upon the nature of the planting and the purpose of the grower.

Pruning can accomplish a lot.  It can start early in the life of a plant, as in the heading back of nursery stock to achieve compactness.  As the years roll by after planting, many fine rhododendrons decline, become leggy, or develop into brush heaps for lack of attention.  Such plants often can be revitalized and improved by judicious pruning and training.  Of course there are limits.  Medium-sized 'Elizabeth' cannot be forced to grow tall by pruning, and giant-sized 'Loderi King George' cannot be dwarfed.  Most rhododendrons respond well to pruning.  Some that do not sprout readily from old wood cannot be much improved.  Others that sprout abundantly should not be opened excessively to light.  If in doubt, proceed cautiously, or seek expert advice.

When to prune. Pruning of hardened wood can be done at any time except during periods of freezing weather.  Early spring generally is best because the new growth then has a full season in which to develop and mature.   Pruning immediately after the blooming period is standard practice.  However, some rhododendrons that bloom very heavily should be pruned prior to bloom to reduce the number of flowers and thus maintain vigor of the plant.  Thinning the flowers also can improve the quality and placement of the ones that remain.

Summer pruning often results in lush sprouts that are subject to aphid injury and may not harden sufficiently to withstand low winter temperatures.  Deadheading, which is the removal of spent flowers, should be done soon after the flowers fade, taking care not to injure the new growth.  This important job helps control insects and greatly improves the abundance and quality of the next year's bloom.  Soft wood pruning, or pinching back, is done during the growing season.  Removal of terminal leaf buds and shoots to promote branching should be done early in the season or from late summer on through fall and winter.

How to start. A good way to start to prune a rhododendron is to crawl under it, look up, and decide what structural changes are needed.  If the plant has been long-neglected, it likely will be necessary first to cut out a tangle of dead branches.  Then remove cross branches and weak wood.  Remove excess branches to give remaining ones room to grow.  Except when layering a plant, remove drooping branches that scrape the ground and provide handy stepladders for weevils to climb and feed upon the leaves.  Remove spindly shoots that sometimes develop along the bole.  Remove sprouts from under-stock on grafted plants.  These sprouts spring up from the base of a plant and produce flowers of a different color, often lavender.  Fortunately modern hybrids are mostly grown on their own roots, and so remain true to color.  In removing hardened wood, make clean cuts, prune flush with the bole or main branches; do not leave stubs.   Thinning the small outer branches is the final step in the pruning process. 

Pruning for compactness. The compact, profusely budded rhododendrons of the nursery trade usually are the objective of commercial growers and landscapers.  These plants are produced by good cultural methods, including de-budding and summer pruning of current growth to induce multiple branching and abundant flowers.  In the home garden, the day ultimately comes when the branches become too numerous and need to be thinned to restore high quality foliage and bloom.  When this occurs, insect damaged, sun-scorched, winter-injured, and scraggly foliage and branches should be among the first to be removed.  Before planting a rhododendron, keep in mind that it is best to select one that will not outgrow the allotted space.  A tall-growing variety just isn't suitable in front of a picture window.  No amount of pruning will make it fit there comfortably and attractively.

Pruning to a single trunk. In some kinds of landscaping, plants are pruned high and trained to a single trunk or a few main stems.  This treatment reveals the structure of the plant and texture of the bark, thus improving the year-around interest and beauty of a planting. An arched canopy over a woodland-type pathway can be achieved by high pruning of adjoining plants.  The openness of a high-pruned plant facilitates the placement of ladders for deadheading and grooming the top, and provides ready access for watering, fertilizing, and mulching.  If a single-trunk plant is the objective from the beginning, heading back can be delayed to encourage height growth.  Also, while a plant is young and flexible, its trunk can be shaped for character by bending.  If a plant has branched very low or has multiple stems, it will be necessary to cut away some lower branches and all except one or a few of the stems to achieve the desired tree-like effect.   The 'Loderi' and 'Naomi' hybrids and many other large varieties respond well to the single trunk treatment. Bushy varieties do not; for example, 'CIS,' 'Bric-a- brac,' R. racemosum, R. williamsianum, and others.

Pruning for special effects. Sometimes it is desirable to prune a group of rhododendrons so that the foliage on one side is allowed to cascade nearly to the ground and that on the other side is pruned high to reveal the beauty of the trunk and large branches.  Rhododendrons pruned in this way exhibit an unbroken bank of foliage or bloom when viewed from one side and a wooded-dell effect from the other.  The exposed trunks should face the north or east, or be protected from the sun by buildings or other plants.

In general the profile of rhododendron plants is regular.  Individually they are difficult subjects to train for asymmetrical or tiered effects.  These landscape effects can best be achieved by grouping rhododendrons of different sizes and textures, or by inter planting them with suitable companion plants.   However, some azaleas, such as R. calendulaceum, are exceptions to the rule in that they respond beautifully to pruning for irregular effects.

Pruning to rejuvenate. Rhododendrons that have outgrown their site or have become tall, ungainly, and sparse of bloom can be rejuvenated by judicious pruning, preferably in early spring.  Don't attempt to do it all at once.  The plant likely will survive one-shot surgery, even make a strong recovery, but it is no way to treat an old friend.  It is better to spread the rehabilitation over 2 or 3 years.  Each year cut back some of the heavy branches to latent buds.  Let the light in to encourage new shoots to form.  Plants that have deteriorated in the top should be cut back and rejuvenated with new growth originating low on the bole.  Prune with the dual objective of retaining the mature structure of the rhododendron and of improving its vigor and capacity to bloom.

Pruning to salvage. When catastrophe strikes and a large plant is broken or otherwise severly injured, don't despair.  It may be salvaged.  In the wild our native rhododendron, R. macrophyllum, often is killed back to the ground by fire, only to sprout again from the root crown and in a few years regain full vigor.  Cultivated rhododendrons that have to be cut back to a stump likewise frequently recover.

Pruning to facilitate moving. Sometimes large, long-established rhododendrons have to be moved.  This is a sizeable but relatively simple job.  For best results, it should be done in the fall or in early spring before new growth begins.  The roots are cut back (pruned) with a sharp shovel, leaving a wide but shallow pad of roots and soil.  Hauled or skidded to its new location, the plant should be set high in loose, well mulched soil.  To ease the shock of moving, some foliage should be pruned to compensate for the loss of roots.   In part this is accomplished by cutting off lower branches that hamper the moving and in part by pruning unneeded upper branches.  It is a good opportunity to shape a neglected plant.

Pruning azaleas. Most of this article concerns broadleaved, evergreen rhododendrons.  Azaleas require relatively less pruning, but some deciduous ones thrive better if the old shoots are periodically cut back to the ground to give new shoots growing room.  Some azaleas that sprout vigorously or send up suckers from the spreading roots need to be thinned occasionally at the ground to prevent excessive bushiness.  Azaleas can be made more compact by heading back the new growth a few inches in early summer.  Some evergreen azaleas will stand shearing, a practice that is common in Japanese landscaping and which produces very dense mounds of foliage.

Pruning for bonsai. The ultimate in controlling growth by pruning is the culture of bonsai.   Some small-leaved rhododendrons and evergreen azaleas are good material for bonsai.  This specialized aspect of pruning and growing rhododendrons is discussed in "Rhododendron Information," a book published by the American Rhododendron Society, and in standard texts on bonsai.

Treatment of pruned surfaces. It is often recommended that the cut surfaces resulting from pruning limbs an inch or more in diameter be treated with pruning compound. Probably more aesthetic than prophylactic in effect, this treatment appears to be optional with the grower.

Basic tools and references. Basic tools and procedures are discussed in standard references such as "The Pruning Manual" by L. H. Bailey and Sunset Magazine's "Pruning Handbook."  Detailed procedures for pruning rhododendrons are discussed and illustrated in "Rhododendrons of the World" by David Leach.

A final word. In summary, it is a myth that rhododendrons should not be pruned.   The essential thing in pruning is to decide upon the purpose.  Then don't be afraid to apply the saw and pruners to achieve the desired result.  The rhododendrons will appreciate the attention and respond to it. 

 

0005 6 Conclusion

It is hard to imagine anything more like a chic lively bouquet with an abundance of blooming flowers than a rhododendron. These tree-like shrubs will not leave anyone indifferent during the flowering period and are not unreasonably considered rather capricious and fastidious in care. At the same time, trimming rhododendrons is no more difficult than other flowering perennials. Although, depending on the variety grown, these amazing beauties in pruning have their own characteristics and subtleties.

Is it possible to prune rhododendrons

It is widely believed that rhododendrons do not need pruning, as they are genetically built to strive for an almost ideal bush shape. And many novice gardeners are so sensitive to their promising plant pets that they get scared at the very thought that they need to pick up a pruner and cut something off from the most valuable specimen of rhododendron.

In fact, the experience of many gardeners, who have been growing various types of rhododendrons in their garden for many years, shows that rhododendrons are not only possible, but also necessary. Like absolutely all plants, they absolutely need regular sanitary pruning. Many varieties also need to correct the form of growth. And more mature plants cannot escape from rejuvenating pruning. It can sometimes be replaced only by a complete replacement of the bush. But not every gardener is ready to easily say goodbye to his pet, who has delighted him with his flowering for many years, only because he has completely lost his shape.

But in order not to bring your blooming pets to such a state, it is better to track all the nuances of possible incorrect growth of bushes every year and help them by forming an attractive crown with the help of pruning.

On the other hand, rhododendrons, unlike many other ornamental shrubs and trees, do not always require mandatory pruning. Indeed, even during transplantation, thanks to a small and compact root system, their roots do not stop their activity for a moment. This means that when moving shrubs with a whole root ball, they do not need the subsequent traditional shortening of the branches in order to balance the "bottoms" and "tops" of plants.

Why you need to prune rhododendrons

As in the case of almost any representatives of the plant kingdom, rhododendron pruning helps to solve many different problems:

When is the best time to prune rhododendrons

The most appropriate timing for rhododendron pruning depends most of all on the purpose for which this or that procedure is carried out. It is most optimal for most varieties to carry out different types of pruning at the very beginning of spring, even before the buds awaken. In some cases, this must be done in late spring or early summer. Most rhododendrons require special pruning after flowering. Finally, it is allowed to prune in the autumn, before the onset of winter cold.

How to prune a rhododendron

There is no single standard technique for pruning any rhododendron. The type, degree and even the time interval for pruning is chosen depending on the species (deciduous or evergreen) and the age of the plant.

All existing varieties of rhododendrons are usually divided into the following categories, which differ in the types of pruning applied to them:

For plants of the first group, it is very important to carry out, from the very first years after planting, annual pinching of the tips of young shoots in late May or early June to form a dense and beautiful crown. In autumn, and throughout the season, you can ruthlessly remove all too frail and underdeveloped branches, as well as shoots growing towards the center of the crown. Anti-aging pruning for shrubs of this group can be carried out 1 time in 5-7 years.

Attention! For a group of shrubs with large leaves, it can be important to wait for bud break and then cut off shoots that have not survived wintering.

For rhododendrons of the third group with small evergreen leaves, shaping pruning is especially important, which stimulates the formation of many young branches. With a strong desire, these varieties can be given almost any shape by trimming. Even form neat attractive "balls" from them. True, this requires a great deal of regular effort and attention on the part of the gardener throughout the year and is best done in warmer regions with mild winters.

In large-leaved evergreen species, very elongated and bare shoots are usually shortened in early spring to stimulate lateral branching. Anti-aging pruning in large-leaved rhododendrons is carried out no more often than after 12-16 years.

How to prune rhododendrons in spring

In early spring, before the buds swell, they usually carry out:

Under the conditions of the middle zone, this period usually occurs in the second half of March or the beginning of April.

After the main snowmelt, it becomes approximately clear how the bushes endured the winter. Sanitary pruning of rhododendrons consists, first of all, in the removal of completely broken shoots, which are cut off just below the break. If the branch is not completely broken off, then if you wish, you can try to save it. To do this, the fracture site is tied with a polyethylene tape, and the shoot itself is tied to the upper branches or a supporting support is placed.

In deciduous rhododendrons, during severe winters, the bark may crack on individual shoots. In these cases, it is necessary to cut off all damaged branches to a living place.

Sanitary pruning also includes the removal of dry and frozen branches and leaves. But in many deciduous varieties it is not so easy to identify them before the buds swell. Therefore, you can wait a bit and prune later, after the leaves bloom.

Initial pruning is usually carried out after the purchase and transplantation of young shrubs to a new location. For evergreen types, it is usually not necessary. But deciduous bushes, if desired, can immediately be given an eye-catching shape.

Spring pruning of rhododendrons is often carried out to form a decorative crown. At the same time, either strongly protruding branches are removed, or those that grow deep into the crown and thicken it unnecessarily. As mentioned above, in deciduous types, it is recommended to additionally pinch young shoots, especially at a young age.

Anti-aging pruning is started when the rhododendron bushes grow so large that they block part of the path on the path or shade the windows of the living quarters. In this case, you should not cut branches that are more than 3-4 cm thick, otherwise the bushes may die. Especially tender are the evergreen large-leaved varieties of rhododendrons. The places of cuts must be covered with a special garden paste or var. Already after 20-25 days, dormant buds may awaken on the branches below the cut and the bush will begin to grow with fresh shoots.

The next year, the restoration of decorativeness and lush flowering is already possible.

It happens that it is necessary to carry out a strong rejuvenation by cutting branches almost to a stump. In this embodiment, the branches are cut at a distance of 30-40 cm from the ground. But you should not cut the entire bush at once. Deciduous species may be able to withstand such pruning, but evergreens have a chance not to survive it and not recover. Therefore, they usually cut about half of the bush in order to complete what they started next year.

How to prune a rhododendron after flowering

If you provide rhododendrons with competent and appropriate care throughout the season, they will delight with abundant flowering and fruiting. But it was noticed that in this case the plants have some periodicity in flowering. Because they spend too much energy on the formation of fruits and seeds. If the bushes are grown solely for the sake of lush and beautiful inflorescences, then immediately after flowering they must be carefully broken out or cut off. Usually, a faded inflorescence is taken with two or three fingers and slightly bent to the side. It breaks easily. You just need to look carefully so as not to accidentally hurt the young shoots that form at the very base of the inflorescences.

As a result, all the available nutrient reserves in the plant will go not to the formation of seeds, but to the laying of new flowering buds and the formation of new shoots. In addition, instead of one, two or three new young shoots are usually formed at the site of the inflorescence.

How to prune a rhododendron for the winter

In winter, rhododendrons are only cut for sanitary and sometimes rejuvenating pruning. In terms of time, it most often falls on the end of September or the first half of October. Depending on the region, this should take place a few weeks before the onset of a hard frost and 2 weeks after the last feeding.

Pruning of rhododendrons in autumn is most often carried out in order to reduce the height of the bushes and ensure their full wintering under shelters.

Advice from experienced gardeners

In order to get the desired result from pruning rhododendrons, it is useful to listen to the opinions of experienced gardeners who have been successfully growing this luxurious shrub for many years.

  1. After any pruning, even sanitary, rhododendron bushes must be watered abundantly and fed with a complex set of fertilizers. The only exception is autumn pruning.
  2. It is best to prune the bushes on a regular basis, checking the correct shape of the plants every year. If for some reason the rhododendron has not been cut for a long time, then you should not carry out cardinal pruning within one season. It is better to do it gradually.
  3. When shaping and rejuvenating pruning in early spring, it is very important to feel for dormant buds and cut the branches above them. Sleeping buds are usually small, pinkish thickenings on the shoots and are quite easy to feel with your fingers.
  4. If rhododendrons have been grown from seed, they should not be pruned at all before the first flowering. Otherwise, it may delay the formation of flowers for another 2-3 years.

Conclusion

Don't be afraid to prune your rhododendrons. For many varieties, pruning is the only way to get beautiful and attractive bushes. In addition, only regular removal of inflorescences helps these beautiful plants bloom profusely every year.

pruning of rhododendrons from A to Z (photo)

Content ✓

Rhododendrons are in many ways special shrubs, unlike most of the crops we are used to. They need a special place in the garden, special soil. And even special agricultural practices. For example, soil mulching is a must, loosening is by no means!

Pruning in this row is an exception, here the rhododendrons appear in the general formation.

With pruning, they have everything like the others, well, or almost everything. There are, as usual, three types of pruning: sanitary, shaping, rejuvenating.

All that is necessary for this article is here >>>

Read also: Landing of rhododendrons - where and with what: neighbors and companions of rhododendron

Sanitary pruning of rhododendrons

are performed according to wintering results early in spring. We remove the broken branches, carefully cutting the shoot below the fault. Small breaks can be pulled together with an elastic bandage, fix this place and substitute a prop under the bruised branch to neutralize its weight (photo 1). If the branch has broken less than half its thickness, there is a good chance that the break will heal. We leave the support under the shoot for a couple of years.

Frozen shoots cut out to healthy tissue. In deciduous rhododendrons, in winters with sudden changes in temperature, the bark often cracks. We cut out such shoots to the living. Sometimes it is difficult to distinguish a frozen shoot of an evergreen rhododendron from a living

stem, in which only the leaves were damaged (“burnt”, but actually dried out under the action of the early spring sun and wind). If in doubt, postpone pruning for a while. Soon it will be absolutely clear whether the escape is alive or not. The leaves of a frozen shoot are dry, dull, and fall off easily. “Burned” leaves on a live branch do not fall off by themselves; at the base of their petioles, buds may already be visible, from which new leaves will bloom. So, in photo 2, only a few shoots in the upper left part of the crown have completely lost the rhododendron, the rest will successfully grow.

Small-leaved evergreen rhododendrons are distinguished by the fact that even a shoot that has completely lost its “burnt” leaves can again completely dress in foliage. Do not rush and cut varieties from this group, unless the affected plant is sitting in plain sight and does not spoil everyone's mood with its condition.

Starter pruning of rhododendrons

As a rule, we buy evergreen rhododendrons in the form of a bush with a beautiful, evenly developed, harmonious crown. Deciduous rhododendron varieties (deciduous azaleas) often don't look as good. They have one or not

how many long, bare and relatively thick shoots with inflorescences at the top and a few short and thin branches. It is better to cut such specimens immediately, trying to give the crown a more or less symmetrical shape (photo 3, 4). Already in the middle of summer, the bush will be much more branched (photo 5), and in the fall you will see that a well-rooted rhododendron has quite successfully laid flower buds over the entire surface of the crown. Thus, we lose in the height of the bush, but win in its shape and quality of future flowering. And such a bush will quickly gain height.

Formative pruning and pinching of rhododendrons

This type of pruning is carried out either in early spring or closer to the flowering time of the rhododendron, i.e. outside the stage of active sap flow. We cut off unsuccessfully located branches, shorten those that weakly or do not give lateral shoots at all, i.e. naked (photo 6). As a rule, formative pruning is easily possible on bushes of deciduous rhododendrons. Many semi-evergreens (such as the Ledebourg rhododendron and the entire PJM series) respond well to pruning, responding with dense branching and a compact crown shape. With evergreen rhododendrons, it is easy to reduce or narrow the crown, cutting into a well-located branch.

A convenient technique is to pinch the shoots of deciduous rhododendrons (photo 7, 8). Thus, we shorten a shoot that is too long and encourage it to branch, achieving a beautiful, evenly developed crown shape. The lateral shoots that appear as a result of pinching have time to lay flower buds.

Rhododendron Rejuvenation Pruning

Rejuvenation pruning, like any other, works well on young rhododendrons. After radical pruning, they grow back easily. Another thing is that young people do not need it. If you are a determined person, then do not be afraid to cut the old bush into a stump, i.e. shorten all shoots to 20-30 cm. The timing for anti-aging pruning is the same - early spring or immediately after flowering. But not all old specimens will easily endure such pruning.

An alternative to planting on a stump of a bush with bare stems, sparse branching, weak flowering and other signs of aging is to replace it. Yes, sometimes it is more rational to replace a bush that has lost its decorative effect, rather than to seek a return of beauty from it with the help of pruning. This is especially true in relation to tall varieties of evergreen rhododendrons.

More densely branched evergreen rhododendrons with a cushion-like habit can often be rejuvenated by pruning. It is performed gradually, shortening up to 15-20 cm by several shoots per season. If successful, buds wake up on old wood and strong young shoots appear (photo 9).

Deciduous rhododendrons can usually be rejuvenated by pruning. In this case, a radical landing on a stump is rarely required, often it is enough to simply reduce the crown by a third or half. In photo 10, a Japanese rhododendron bush, which is over 35 years old.

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