Frozen rhododendron dry brown leaves. Why do rhododendron leaves have brown leaves? Light and temperature

I transplanted it into partial shade, but new leaves do not grow, the buds dry out... It is clear that the bush is alive. I've already fed it in the spring. The soil is wet, I spray it often... What should I do? I want to save the bush! Help with advice please!...)

Properly planted rhododendrons take root well. If the soil substrate was made with high quality, they will not require special care.

During the hot and dry summer and even autumn months, it is necessary to ensure that the soil under the bushes does not dry out. However, do not get carried away - excessive watering is harmful to them.

Since in the mountains these plants live in conditions high humidity air, then, as a rule, they respond very well to spraying the entire bush with leaves and flowers. Naturally, this should be done not under the scorching sun and not ice water.

It is best to water with rain or river water. Water from an artesian well or water supply contains a lot of calcium and magnesium salts - in this case, the soil will begin to alkalize and become saline, and rhododendrons will lose their decorative properties. (At first, nothing seems to happen, but after 2–4 years, hard water will do its job.)

To prevent the soil substrate from becoming alkalized, the water for irrigation must be acidified - preferably with sulfuric acid. It is difficult to indicate the exact concentration of acid - it depends on the degree of water hardness. The easiest way is to use litmus indicator paper. The pH value of water should be 3.5–4.5.

Withered inflorescences, which reduce the decorativeness of the plant, need to be broken off or carefully trimmed, preserving the axillary buds of the plant. upper leaves. This contributes abundant growth and the flowering of rhododendrons next year.

In the spring, after 1-2 years, add to the soil in trunk circle a bucket of rotted manure and peat or compost and peat and cover it to a shallow depth. In addition, mineral fertilizers are added in dry form: 1 tablespoon each of ammonium sulfate, superphosphate, potassium sulfate. All fertilizers are mixed with bedding.

The root system of rhododendrons is shallow and compact, so loosening must be done very carefully, without digging up the tree trunks. To protect the soil from drying out, it is recommended to mulch the tree trunks with a layer of crushed peat or tree bark or pine litter, which has an acidic reaction.

Most likely you fed it too early, or over-fertilized it (it needs to be replanted!

The shelter was not of good quality and was affected by fungus.

Treatment with “iron chelate” with a weak solution or its substitutes.

They collected pine needles from the forest and sprinkled them around it, embedding them in the soil. and fell asleep on top. Provide watering and wait for the buds to start growing. After they start in a week, you begin to feed once a week. and treat with that product once a month

I had four rhodendron bushes. It was fine for two years, BUT! Then the first one died, the next year the second, now the third, and after wintering the branches were barely alive, and yet he died. The last one remained, half dead. I dug it up, removed the dry roots and planted it in bare peat, and a week later I acidified the soil with citric acid. It seems to be holding up somehow for now, we'll see what happens. Now I’m analyzing my mistakes, I think that they died because of the soil: it was not acidic enough. So you try to acidify the soil for it before it disappears completely.

The plants known as rhododendrons are unique shrubs. Azaleas and rhododendrons bloom in May and June, so they are optimal choice for people who expect beautiful and impressive flowers at the beginning of summer. Rhododendrons are evergreen shrubs, while azaleas shed their leaves in the fall. They also vary in height and flower appearance, which are exceptionally good.

Rhododendron is a type of shrub belonging to the heather family ( Ericaceae). In the natural environment plants of the genus Rhododendron found mainly in mountain forests of Asia and Northern and Central America. They inhabit places with high humidity. Azaleas have soft, slightly hairy leaves that fall off in the winter, making them more frost-hardy. “Proper” azaleas are evergreen, and in winter they cannot tolerate the effects of cold, drying winds.
Both species plant between April and mid-September. They are bought in containers. Before we make a decision on a specific purchase, it is worth checking whether the substrate in the container is sufficiently moist. If it appears too dry, it may mean that the plant has dead roots because they are not getting enough moisture. You also need to carefully examine the leaves and shoots. They should be free of discoloration, spots, cavities or other alarming changes that may indicate rhododendron disease.

Planting rhododendron

In general, rhododendrons will thrive best in areas of the country that experience relatively mild and wet winters. In the garden itself, rhododendrons will be comfortable in partial shade or shady place which is protected from the wind. Best position by the water, where high humidity. In turn, azaleas are planted in a well-lit or slightly shaded place.

Rhododendrons need an acidic substrate and fertile soil.

Unfortunately, this type of soil is not very common in gardens, so it must be properly prepared before planting. Fill a hole 50 cm deep and about 1 meter wide with 10 to 20 centimeters of drainage in the form of gravel or mulch. Then a layer of peat mixture, composted bark and compost in equal proportions. After planting the bush upper layer the substrate is additionally mulched with a five-centimeter layer of bark. This will ensure sufficient soil moisture and minimize weed development.

Well prepared soil and correct landing will create ideal starting conditions for the growth of rhododendrons.

Planting correctly

• 1. A healthy seedling has thin white roots piercing the earthen lump. For their further normal development, loose soil enriched with peat is necessary.
• 2. Before planting, immerse the root ball in water and keep it there until the bubbling stops.

• 3. The planting hole should be 2 times wider than the root ball of the plant. Use a garden fork to loosen the soil in the planting hole.
• 4. To fill it, a mixture of garden soil and peat (50% each) or special soil for rhododendrons is suitable.

• 5. Important: do not plant rhododendrons too deep. Top part the coma should be at the level of the soil surface.
• 6. Mulch the soil around the plant with a layer of 1 to 3-5 cm. For these purposes, use compost made from bark or pine needles aged for at least six months, as well as well-rotten oak or beech leaves.

• 7. After planting, fertilize the plants. The ideal feeding is a mixture of horn shavings and mineral fertilizers or special fertilizers for rhododendrons. Distribute the fertilizer evenly over the surface of the ground and water the seedling well. If you plant a plant in the fall, do not feed it, but wait until spring.
• 8. Water the rhododendron thoroughly, but do not overdo it (so that there is no stagnation of moisture).

Watering is important not only after planting, but also in the following months, until root system the bush will not strengthen. Rhododendron planted in dry places needs to be watered more often. Watering is also necessary after each application of fertilizers.

Substrates, fertilizers and mulch

For health and abundant flowering Rhododendrons require loose, humus-rich soil. You can improve clay or calcareous soil in your garden by adding peat and humus. Special soils for rhododendrons or peat substrates are ideal. Remember that fertilizers must meet all the needs of rhododendrons. Fertilizers vary in quality, so we advise you to buy products famous manufacturers. But it is good to use pine bark as mulch.

Lime is no longer scary

Owners of gardens with calcareous soil can now also grow rhododendrons. As a result of many years of work, breeders managed to obtain a rootstock tolerant to lime (INCARHO rhododendrons). Many popular rhododendron varieties are grafted onto this rootstock. True, they are not completely immune to lime, but they show a certain tolerance to it. Experts recommend these varieties for gardens with soils whose pH ranges from 5.5 to 7.0.

Caring for rhododendron in open ground

The soil under rhododendrons should not be dug up to avoid damaging the roots. Loosening with a thin hoe is allowed. However, it is necessary to regularly remove weeds before they reach large sizes, since removing large weeds can also damage the small roots of the rhododendron.

Rhododendrons need feeding with special preparations, which can be purchased at garden stores. Delivery nutrients should occur in spring and early summer. However, be careful not to extend this period as the plants will not have time to prepare for winter.

Fertilizers for growth and abundant flowering

Rhododendrons growing near deciduous trees do not need additional fertilizer; its function is performed by the foliage that falls every year. However, in most gardens rhododendrons still need regular feeding mineral fertilizers, especially if the bushes are still young.

1. It is best to fertilize rhododendrons for the first time in April-May, when the plants are actively growing.
2. The second - more important - feeding is done after rhododendrons bloom, when new shoots appear on the plants (usually in June-July).

Approximate figures: for a plant 40 cm high and wide, about 15-20 g (half a tablespoon) of fertilizer is required in spring and summer, for a plant 150 cm high, 80-100 g respectively.

Do not use liquid fertilizers; rather, use granular, slow-release, or specially formulated fertilizers for rhododendrons.

Careful rhododendron care also includes an annual pH test of the substrate. If necessary, we also mulch the substrate with a mixture of bark and acidic peat.
After the rhododendron flowers, it begins the process of producing seeds. Carefully pinch off the inflorescences immediately after they wilt. Thanks to this, the plant will not waste energy on ripening seeds, but will save energy for the formation of new shoots and flowers next year. In addition, rhododendron bushes take on a more well-groomed appearance.

Trimming

Is it possible to prune rhododendrons?

It’s better not to prune at all - rhododendrons look more picturesque over the years

It is better not to prune them at all - rhododendrons look more picturesque over the years. If you have to trim a bush that is too tall, it will soon produce new shoots even on old woody branches (see photo). Keep in mind, however, that these slow-growing shrubs will take several years to grow back to their previous height.

In spring, dried and frozen shoots should be cut out. Young plants can also be stimulated at this time by lightly pruning them. Old bushes that have lost a lot lower leaves and look ugly, it is worth rejuvenating by cutting out all shoots, even thick ones. After the branches are reduced, in a few weeks many young branches will grow from the dormant buds. If you are not sure that the bush is strong enough to withstand such a radical cut, you can rejuvenate half the bush in the spring and the rest the following year.

Shelter from frost and wind

Drooping leaves are not a sign of frost damage

Rhododendrons grow well in temperate climates with warm winters and high humidity. In such conditions, even in the cold season, metabolism occurs in their evergreen leaves. But the cold winters Central Europe are not entirely suitable for rhododendrons - on sunny days, the process of photosynthesis begins in the leaves, and the roots cannot absorb enough water from the frozen soil for metabolism, and the leaves begin to dry out. Therefore, for rhododendrons, the winter sun sub-zero temperature more dangerous than the frost itself.

For sensitive varieties and standard plants, it is advisable to use shelters that create shade. They protect plants from the wind and, by creating shade, prevent leaf dehydration. It is best to make such shelters from breathable materials, such as agrofibre, otherwise mold may appear underneath them. Dehydration is especially dangerous for container rhododendrons, so they should be watered generously in winter.

Rhododendrons growing in the shade, for example under the canopy of trees, usually do not need to be covered for the winter.
Drooping leaves are not a sign of frost damage, but a natural reaction of the plant to it. The tent will protect you from wind, cold and winter sun, which can dry out the leaves when there is frost on the soil. For standard plants, both the crown and the trunk should be covered for the winter.
Small “LEGS” under tubs and pots will ensure excess water drains.

Optimal watering

Rainwater is ideal for irrigation as it does not contain lime.

Rhododendrons prefer evenly moist soil. They are equally sensitive to both drying out and waterlogging. When watering you need to know when to stop: a large number of water washes away nutrients and leads to rotting of the roots; with insufficient watering, the bushes wither and dry out. If the leaves droop during the day due to the heat, this is normal; plants usually recover overnight. For irrigation, it is better to use rainwater, which, unlike tap water, does not contain lime. A layer of mulch prevents water evaporation and retains moisture in the soil. They perform the same function ground cover plants, creating a favorable microclimate. Computer controlled is suitable for dry soil drip irrigation, evenly moistening the soil.

Important: evergreen rhododendrons should be watered in winter.

Reproduction by layering

After flowering has finished, lightly cut the bark of a branch located close to the ground under the whorl of leaves. Bend the branch so that its cut down can be placed in a hole filled with humus to a depth of 5 cm. Carefully secure the branch with a hook and make a support. Next spring rooted cuttings can be separated with a shovel and transplanted to permanent place in the garden. After planting, do not forget to water the young plant well.

Caring for rhododendron after flowering

• 1. Removing faded flowers

Removing faded flowers is a necessary condition for rhododendrons to form new ones flower buds and leaves next season. Faded inflorescences are removed in the summer, when rhododendrons finish their flowering period, leaving new leaf buds underneath. It is better to pick off the inflorescences by hand (not with scissors). Thanks to this treatment, the seed production process is not carried out, and the nutrients can be used by the plant for growth, development and creation of new buds. You can also cut off dead, dry shoots.

• 2. Removing fallen flowers and leaves

Must be removed carefully fallen flowers and leaves from under the bush. Especially if they are affected by lesions, they must be removed and burned. The litter will rot, providing nutrients for the development of fungal diseases.

• 3. Fertilizing rhododendrons after flowering

Rhododendron after flowering feels a lack of nutrients, which were used in the flowering process. In summer and autumn, phosphorus-potassium fertilizer should be used. During this period, plants do not need much nitrogen. Mineral fertilizers - potassium sulfate and superphosphate or available ready-made fertilizers for rhododendrons, containing all the necessary ingredients that also affect soil acidification. In addition, foliar fertilizers containing microelements such as iron and magnesium are used, which affect the intense color of the leaves. Fertilizers should be applied no more than the recommended doses.

Providing nutrients will allow the rhododendrons to set many new flower buds.

• 4. Watering rhododendrons after flowering

With excess water, plants are susceptible to fungal diseases. However, if there is a drought, with more sunlight and hot weather, which often happens in the summer months, after the rhododendron blooms, the bushes should be watered. In particular, plants that grow in light and permeable soils require watering. During other periods, precipitation water is sufficient and healthiest for plants. Plants need more water before winter sets in. With heavy frosts, they will no longer be able to collect it, and this is necessary for the proper development of leaves. In the absence of water, the leaves wilt and turn brown. Therefore, rhododendrons should be watered abundantly immediately before the onset of frost.

• 5. Sheltering rhododendrons for the winter

Most rhododendron varieties are frost-resistant, even down to -30°C. Some varieties are less frost-resistant (down to -20°C). The best shelter For winter there is snow, but it is not always present. It is advisable to cover young rhododendrons planted this year. You can use spruce branches, straw mats or agrofibre. Young and older shrubs are well mulched for the winter with pine bark, which additionally acidifies the soil. There is less soil freezing and less water loss. Roots are less vulnerable to frost damage. Rhododendrons that will survive winter in good condition, will bloom again in a year.

Diseases and pests of rhododendron

Why do rhododendrons get sick? Rhododendrons have enough high requirements to cultivation, and our climate is not conducive to these plants.

Rhododendrons can be affected by different types of fungi. As a result, the leaves at the edges or tips turn brown, dry out, and eventually fall off. In addition, shapeless heels often appear on the leaves. With the help of fungicides, these symptoms can be removed, but the reason for their appearance - the unfavorable living conditions of the plant - will remain. Sometimes it's just good feeding leads to the recovery of rhododendrons. Also monitor soil acidity.

Kidney death

Brown buds with black fluff indicate fungal infection. Such buds should be removed.

Unfortunately, a common disease of rhododendrons is bud death. It is caused by a fungus carried by rhododendron cicadas. Buds affected by the fungus turn brown and fall off. It is impossible to destroy the fungus, but fortunately it does not spread to the rest of the plant. Pluck and destroy affected buds.

A yellow sticky piece of paper (photo) attached to a plant branch will help you check if there are insects on the rhododendron.

To prevent fungal damage to the kidneys, you must first fight cicadas: examine the rhododendron, usually these insects sit on back side leaves.
It is best to destroy cicadas in the early morning, when the insects are still inactive. Treat the leaves with an insecticide: you need to spray the plants immediately after the cicadas appear in mid-May; if necessary, repeat the procedure after 2 weeks.
Green-yellow cicadas, about one centimeter long, sit mainly on the underside of leaves. Small dots on the leaves are traces of their vital activity - they indicate the presence of “uninvited guests”.

Wasting, chlorosis

With chlorosis (depletion), rhododendron leaves turn yellow, but the veins remain green. This disease occurs most often due to insufficiently acidic or very dense soil that does not allow air to pass through.
Most often, chlorosis begins a few years after planting, when the roots extend beyond the landing pit and fall into the calcareous soil. Help: transplant the plant to a more suitable place or acidify the soil underneath it by lowering the pH value.

Frost

Even if the rhododendrons survived low temperature winter is relatively good, they are sensitive to late spring frosts. A light frost in May can severely damage the young leaves and flower buds of the plant that have already appeared. If new shoots emerge from the spare buds, the plant will not die, but it is better to remove the darkened branches of the rhododendron.

Insatiable weevil

Weevil is a dangerous pest

Semicircular, eaten away areas on the sides of the leaves are a sign of a pest.

More dangerous than the beetles themselves are their larvae, which eat the roots of shrubs. They are yellowish-white in color, with a brown head.

If the lower old leaves of rhododendrons have become completely yellow (as opposed to those affected by chlorosis) and are gradually falling off, the plant is most likely lacking nitrogen. It is one of the essential plant nutrients, and flowering rhododendrons especially need it. Help: Apply to soil immediately complex fertilizers. It’s best to feed the bushes every spring with horn shavings - this will prevent a lack of nitrogen.

We consider caring for rhododendron in open ground spring, summer, autumn and winter. The following are described in detail: watering, fertilizing, fertilizers, pruning and flowering, as well as preparation for winter, pests and diseases.

Plus regional features: Moscow region, Ural, Siberia, North-West (Leningrad region) and the Middle zone.

How to care for rhododendron in the garden in spring and summer?

Planting lays the foundation for further plant care in open ground. If it is planted in suitable place into the correct soil mixture, then further care much simpler. We described how to do this correctly in a special material - see at the bottom of the page.

In spring, the flower awakens after winter and you need to help it recover, save it from drying out and rotting. Caring for rhododendron in spring and summer consists of regular watering and spraying, fertilizing, pruning and disease prevention.

Saving the kidneys from drying out

1. After active snow melting (mid-March - early April), the soil can slowly thaw and the sun can become hot. The evaporation of moisture from the buds and leaves increases, and the roots are constrained and have not awakened.
2. Therefore, free the bush from last year’s frozen mulch (you can loosen it and remove half the layer) so that the ground near the roots thaws faster.
   This will allow the roots to start working and save the buds from drying out. It is especially important to remove the mulch quickly if the winter was cold or with little snow.
3. Water " pink tree» hot water(even boiling water) and spray warm water.
4. If the rhododendron overwintered without shelter, then make a protective shield from the sun on the south and west sides. Drive in the stakes and stretch the fabric. Read more in the article “Preparing for winter” - link at the bottom of the page.
5. After complete thawing of the soil to a depth of 20-30 cm (beginning - mid-April), on a cloudy day or in the evening, remove the protective cover (covering material) or winter shelter.

If you still find signs of burns on the shoots, the buds have dried out and do not begin to grow, then spray them with warm water every day, and every 3-4 days with a growth stimulant (Zircon, Epin, etc.).

Rhododendron flower buds in spring after removing winter cover

Rhododendron pruning

Trim the plant only if necessary (once every 2-5 years): if you need to update an old specimen, shorten a bush that is too tall, or remove frozen stems.

Classic formative pruning is not necessary because the natural shape of the plant is correct and attractive in 99% of cases.

Rules

• Carry out pruning before the buds swell (mid-March - early April).
• The cut should be made directly above the dormant growth point - a small pinkish swelling-thickening. Be sure to learn how to identify them.
• Treat each cut with garden varnish.
• Provide pruned specimens with regular watering and feeding.

Species features

1. Small deciduous species need to be rejuvenated every 5-7 years, and large ones (Canadian and others) every 14-18 years.
2. Small-leaved evergreen species up to 4-5 years old need to be pruned to stimulate branching. If desired, you can even create a ball shape. Since powerful flowering is observed even in 20-25 year old branches, they are rarely pruned.
3. Evergreen species with large leaves are pruned every spring by 1-3 shoots from their total number so that the lateral branches develop better. Otherwise, in a few years these shoots will become ugly and long branches with leaves only at the top. The leaves themselves will become small and the flowering will be weak.

How to trim a large bush?

Trim the shoots in places 2-4 cm thick near dormant buds. After 20-25 days, the dormant buds will wake up and begin to grow, and next year the decorative appearance of the bush will be restored.

How to rejuvenate a bush?

To rejuvenate very old bushes or those seriously damaged by frost and wind, cut the branches at a level of 30-40 cm from the soil near dormant buds: first one half, and after a year the other, to facilitate rehabilitation.

Rejuvenating pruning of evergreen rhododendron after an unsuccessful winter

Advice

If you want a thick and spreading deciduous rhododendron, then pinch out seasonal shoots in June for the first 3-4 years after planting, and cut off all weak stems inside the crown in September.

How to water rhododendron?

A deficiency or excess of water is undesirable for a plant. Prolonged lack of water prevents the seasonal growth of shoots, impairs flowering and reduces decorativeness (leaves dry out, turn yellow, and old leaves fall off en masse).

• Leaves signal a lack of moisture. Due to the loss of turgor, they droop, wither and acquire a matte tint. Lack of watering aggravates the situation: the leaves turn yellow, brown (edges and central vein), dry out and die.

“Rosewood” is harmed by stagnation of water, and it is sensitive to excessive amounts of moisture in the soil. This disrupts the development of the flower, since little oxygen reaches the roots. At the same time, the leaves also turn yellow, wither and fall off.

The frequency of watering is affected by the planting location, the composition of the soil mixture and climatic conditions. Rhododendron, planted in a favorable location and in the correct soil mixture, needs less frequent watering.

Ideally, determine the frequency of watering yourself based on the condition of the leaves and the amount of precipitation. As soon as they become dull (the shine has disappeared) and drooped a little, they need moisture. Therefore, watch for these signs and accumulate your personal experience.

The most important periods for watering: active growth and development (April - mid-July) and preparation for winter (mid-September - November).

April - July

During the period of intensive growing season, during the flowering period and after it, there is an increased need for moisture; the root ball should not be allowed to dry out. Therefore, every 4-7 days, water 10-14 liters of water into the tree trunk circle under an adult bush.

If spring and summer are hot and there is little rain, then you need to water more often and supplement with spraying. Every 2-3 days, early in the morning or late evening, spray the leaves with water.

August and September

At the same time, in August and September it is necessary to water less often - 10-14 liters of water every 8-12 days, otherwise secondary growth of stems is possible.

Loosening the soil

Others believe that it is advisable to weed 3-4 times over the summer, but very carefully: loosen 1-2 times in one place 3-4 cm deep.

Adviсe

Water for watering and spraying the “rose tree” should be soft and acidified (pH 4.0-5.0) - a teaspoon of citric or oxalic acid per 10 liters of water.

Feeding and fertilizers

Proper feeding ensures good growth and development, powerful and beautiful bloom, and also increases the resistance of rhododendron to adverse external factors(pests, frost, diseases, wind).

• The most important periods: March - April and immediately after flowering.

It is advisable to use liquid fertilizer. In this case, the nutrient solution requires a low concentration, since rhododendron grows slowly and the roots lie close to the surface.

Signs of need for feeding

Light, pale leaves without shine. Yellowish-green shoots. Small seasonal increase. Weak or no flowering. Old leaves fall off en masse in August.

Change in leaf color is the first symptom of nutrient deficiency.

What fertilizer to use for rhododendrons?

A good option would be to use a special fertilizer; it has a balanced composition of mineral elements and rapid solubility. You can also use complex mineral fertilizers, for example “Kemira-universal” and organic.

Organic fertilizers

According to experts, organic fertilizers are more preferable because they are better absorbed than mineral ones and improve the soil (looseness, moisture and air permeability).

• Of these, it is better to use: blood meal, semi-rotted cow dung and horn flour. Do not use: bird droppings, pig and horse manure.

Fill the semi-rotted manure with water 1:15-20 and leave for 3-4 days. Before fertilizing, water the bush (the root ball should be completely wet). Can only be used from April to the end of June.

In spring or autumn, semi-rotted manure can be scattered near the bush in a 4-5 cm layer on the surface of the ground, so that with incoming moisture from rain or melting snow necessary elements fueled it.

Mineral fertilizers

Since rosewood prefers acidic soils, it is necessary to use acidic fertilizers. These are mainly: potassium nitrate, superphosphate, potassium phosphate and sulfates - ammonium, potassium, calcium and magnesium. Fertilizers containing chlorine are prohibited.

The nutrient solution for feeding should be 0.1-0.2% i.e. 1 gram of substance per liter of water, and potash fertilizers - 0.05-0.1%.

Feeding schedule

After winter, rhododendron needs to be fed, and if the acidity level has increased (“”), then the soil needs to be slightly acidified.

To acidify, add a tablespoon of vinegar, oxalic acid or citric acid. Especially if the bush grows on loamy or sandy soil.

1. After the snow melts (late March - early April), water the plant with mullein infusion or dissolve 20 grams of ammonium sulfate, 6 grams of potassium sulfate and 8 grams of superphosphate in 10 liters of water.
   After this, immediately mulch the tree trunk circle with a 6-8 cm layer of pine sawdust or peat.
   Such mulch will reduce acidity, retain moisture longer and prevent the active growth of weeds. The base of the bush cannot be covered; it is better to sprinkle it with coarse sand to prevent rot and stagnation of water.
2. After 20-25 days or 10-14 days before flowering (beginning of budding). Same composition.
3. During flowering or immediately after it. To make the bush bloom more powerfully or regain its strength: 8 grams of superphosphate and 6 grams of potassium sulfate per 10 liters of water.

To maintain the required soil acidity after the first and second fertilizing, it is advisable to water with the following solution: 8 grams of potassium phosphate and potassium nitrate per 10 liters of water. If you watered it with mullein infusion, then there is no need.

2nd option

1. Before flowering. Apply 20-30 grams of special fertilizer or Kemira Universal fertilizer (2-3 grams per liter) under the bush. In any of the options, add nitrogen for growth: 5-10 grams of carbamide (urea) or ammonium nitrate.
2. Immediately after flowering. Similar feeding.
3. Late July – early August. 30 grams of superphosphate, 15 grams of potassium sulfate + 10 grams of complex mineral fertilizer per 10 liters of water. Fertilizing accelerates the lignification of shoots and prevents their growth in late summer - early autumn.

3rd option

1. After the snow melts (late March - early April). Scatter over the surface of the earth per 1 m2 or a specimen above 100 cm: 40 g of ammonium sulfate and 20 g each of potassium sulfate and superphosphate or 50 g each of ammonium sulfate and magnesium.
2. After flowering (late May - early June). 20 grams of ammonium sulfate and 10 grams of potassium sulfate and superphosphate.

This option is much lighter than liquid fertilizers and suitable for those who have a large number of plants planted.

Adviсe

• Do not use fertilizers that reduce soil acidity, such as wood ash.
• Do not use slow-release granular fertilizers as they may cause secondary growth of stems in August that will freeze in the winter. They are designed for the European climate with six warm months a year.
• If secondary growth does begin, then spray the bush with potassium sulfate - 10 grams per liter of water.
• The editors of the Flower Festival magazine recommend using more organic fertilizers than mineral ones.

Disease Prevention

At the end of April - beginning of May, spill or spray the “rose tree” with copper-containing fungicides (copper oxychloride “HOM”, copper sulfate).

Preventive treatments are especially important for the species: Canada, Ledebur and evergreen species.

Rhododendron blossom

All gardeners expect unique and powerful flowering of the bush every year. Despite his attractive appearance all season long, it is the luxurious inflorescences that create maximum decorativeness and captivate millions of eyes.

When does rhododendron bloom or flowering time?

Flowering times depend on climatic conditions specific area and year, variety and condition of the plant. Typically the flowering period lasts from April to June. Early flowering species (Daurian, Canadian, Ledebura) bloom in mid-late April and in early-mid May they stop blooming.

Then the evergreen large-leaved species begin to bloom in early to mid-May, and are soon joined by deciduous species and varieties based on them.

How long or how long does rhododendron bloom?

Flowering period for different types and varieties lasts a different number of days, on average 16-20 (30-45). The duration of flowering depends on many factors: amount of light, temperature, species characteristics, amount of nutrients, etc.

Care after flowering

To ensure that the “rose tree” blooms profusely every year, break out the inflorescences immediately after they have bloomed (there will be no seeds!). The inflorescence at the base breaks off effortlessly with your hands, but you need to be careful not to damage the young shoots.

This procedure will help the bush direct all its forces to the formation of lateral buds and abundant flowering next season. It will also become more lush, because not one, but 2-3 young shoots will appear at the base of the inflorescence.

Then water the plant generously and feed it with potassium-phosphorus fertilizer.

• It is especially important to break out the inflorescences of large-leaved species.

Rhododendron Katevbinsky "Grandiflorum" (Grandiflorum)

Rhododendron: care in autumn and preparation for winter

Caring for rhododendron in the fall comes down to preparing for wintering, which includes proper watering, disease prevention, mulching and, if necessary, protection with covering material or construction of a shelter.

Watering

In September we water more often than in August, and in October we need abundant watering before winter, especially in dry autumn and for evergreen species and varieties. Water them until the November frosts. If it is not possible to go to the country in November, then it is better to plant only deciduous rhododendrons.

In rainy autumn, often in the Moscow region, Leningrad region, watering is rare.

• A sufficient amount of moisture in September - October - November contributes to the successful wintering of the plant, increases its endurance, and drought reduces resistance to external negative factors.

Disease Prevention

At the end of September - beginning of October (before frost), treat the plant with Bordeaux mixture, copper sulfate or a copper-containing fungicide to prevent fungal diseases.

Preparing for winter and sheltering for the winter

By the beginning of October, the bush should have formed flower (large, round) and growth (smaller and sharper) buds for the next year. The main task is to preserve these buds until spring from freezing, burns, breakage and drying out.

• Since this is a very serious point in caring for rhododendron, we covered it in a special article - see the link at the bottom of the page.

Pests and diseases

Depending on the species and variety, the susceptibility of rhododendrons to diseases and pests differs. According to the observations of gardeners, in an open and sunny area, evergreen species are more likely to suffer from pests and diseases than in light partial shade.

At the same time, a strong and strong plant is less susceptible to encountering “ uninvited guests" That's why, proper care in open ground behind rhododendron and here it is of decisive importance.

Pests

Possible problems during cultivation

Why does rhododendron brown leaves?

Often the leaves become Brown(central vein and edges) not when affected by any fungal diseases, but due to lack of moisture. This is the main factor.

The tips of the leaves turn brown and dry out due to sunburn in the spring or lack of moisture due to the heat.

Why do the leaves turn yellow?

In addition to a lack or excess of moisture, the reason often lies in low acidity of the soil. Set aside and acidify the water before watering, feed with a buffer solution - the composition in the first fertilizing option.

Flower buds fall off

Reason – heat air and low humidity.

Why do the leaves curl?

Flowers wither due to insufficient watering or low humidity. Spray the plant more often.

If this happened after the first autumn frosts, then there is no need to worry - this is a natural process. Read about this in the article “Preparing for winter.”

ADDITIONS TO THE ARTICLE:

We wish you proper development and beautiful flowering!

Improper substrate preparation and chlorosis

Most common mistake When planting rhododendrons, there is inappropriate soil acidity, high salt content in the soil, insufficient or excessive soil moisture. If the acidity of the soil does not meet the requirements of the plant, chlorosis occurs. In alkaline and even neutral substrates, iron and magnesium, which play an important role in the formation of chlorophyll, are in a form that is not absorbed by rhododendrons. This leads to stunted growth and disease. An incorrectly selected substrate ultimately leads to the death of the plant. Chlorosis usually occurs when the pH of the substrate is above 7.

Symptoms: in plants affected by chlorosis, the leaf blade between the conducting veins becomes light green or yellowish-green. In the initial stage of the lesion, the veins still retain a dark green color, but later they also turn yellow. With severe chlorosis, all young shoots become yellow or pale yellow and are easily burned in the sun. To eliminate chlorosis, the pH of the medium should be brought to 4.0-5.0. Feeding with iron chelates is also recommended.

Insufficient or excessively high air or soil humidity

Lack or excess of light

With a lack of light, the shoots become elongated, the decorative effect decreases, and the plants stop blooming. With too much light there is a risk of sunburn, disease and pests.

Sunburn

This disease is usually observed in the spring after severe frosts or at the end of winter when there are sharp fluctuations in temperature day and night. Most often, burns appear when the temperature drops to -15° C or more at night, and during the day, in the bright sun, the surface of the leaves heats up significantly and begins to actively evaporate water.

Symptoms: brown, dry, irregular spots appear on the leaves.

To avoid sunburn, rhododendrons should be planted in semi-shaded areas. If plants are planted on open place, in winter, artificial shading is required. Sometimes sunburn appear not as spots, but as a brown stripe running along the main vein of the leaf. During severe frosts, they may also be damaged. flower buds rhododendrons. In this case, they become brown and dry out.

Winter drying of rhododendrons

Nitrogen starvation

With a lack of nitrogen, the entire leaf blade of rhododendrons becomes light. New shoots grow weakly, small leaves develop on them, and flower buds do not form. In mid-summer, or in August, the leaves of previous years begin to turn very yellow, then become reddish-brown and most of them fall off. By the end of summer, only the leaves of the current year remain on the plants, although under normal growth and nutrition conditions on an evergreen plant, the leaves remain for four years. Specified signs indicate that the plants are starving, and, in particular, experience an acute lack of nitrogen. Most often, the disease manifests itself in rhododendrons grown on lungs. sandy soils. If rhododendrons are regularly fed annually, they will not experience nitrogen starvation. When the first signs of nitrogen starvation appear, nitrogen fertilizing (ammonium sulfate or potassium nitrate) should be applied.

Soaking rhododendrons

The leaf blade becomes grayish-green, matte. Leaves without visible external reasons fall off. New shoots become soft, leaves wither, and the root ball is destroyed, although the roots at the root collar are not damaged. These signs indicate that the aeration of the root system is clearly insufficient. Wetting of rhododendrons usually occurs if they are grown in heavy, clay soils with poor drainage, and also if they are watered abundantly and often after transplantation. To avoid rhododendrons getting wet, they should be planted in a specially prepared water- and breathable substrate in a well-drained place. Watering throughout the growing season should not be excessive.

Snowbreaker

Under heavy snow loads, rhododendron branches may break. Evergreen varieties and species are especially susceptible to such damage. Tall plants should be shaken off during and after wet snow. Some authors recommend the construction of winter shelters.

With a disease such as rhododendron spotting, the leaves of the plant become covered with spots. The size, color and shape of these spots can be different, and it depends on the causative fungus: gray, brown, yellow, black, angular, vague, round, with a black border. A gray coating may appear on the upper side of the leaf. A disease like rust on rhododendron appears on the lower part of the leaves in the form of dusty yellow, brown or red pimples.

Rhododendron diseases are a real concern for gardeners

Fungal diseases of rhododendrons

The fungi also cause the shoots to die, and the buds of rhododendrons are affected, which first turn brown and then die. Then, the same thing happens with the leaves, and then with the shoots of plants. Such diseases need to be treated with drugs based on copper; treatment cannot be carried out with humid air, as the leaves may get burned.

Rhododendron diseases caused by external factors

Rhododendron leaves dry out and fall off

The winter drying out of rhododendrons is similar to the death of shoots; the leaves of evergreen species first curl, then dry out and die; in fact, this is the result of a violation of the plant’s water metabolism. This disease can be prevented by watering evergreen rhododendrons abundantly before wintering, and if signs of the disease appear in the spring, then after the soil has completely thawed, the plants need to be watered and sprayed generously.

Rhododendron is a whimsical plant

Rhododendron leaves turn yellow and fall off

Nitrogen starvation is provoked if rhododendrons are grown on sandy soils - the leaves become significantly lighter and smaller, the growth of young shoots stops, and flower buds do not form. At the end of summer, the leaves on evergreen species begin to turn yellow and then fall off. In this case, the plant needs replanting or systematic feeding with mineral fertilizers, which are based on nitrogen.

Rhododendron root rot

External signs of a disease such as root collar rot are similar to those of rhododendrons that become wet - the shoots become soft, the leaves have a dull, grayish tint and begin to fall off. This disease usually develops if it grows in clay soils with poor drainage. In this case, the rhododendron needs to be transplanted into moisture- and breathable soil.

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