How to grow rhododendrons? A detailed guide to growth habits and planting methods

In China, they are distributed in all provinces and regions north and south except **, with the greatest number of species in Yunnan, Tibet and Sichuan, which form the world distribution center of the genus Rhododendron.

The genus Rhododendron has many species and greatly differing habits, but most species originate in high-altitude areas, prefer cool, humid climates, and dislike extreme heat and dryness. They require acidic soil rich in humus, loose, moist and with a pH of 5.5 to 6.5. Some species and horticultural cultivars are more adaptable, tolerating drought and poor soil, and can also grow in soil with a pH of 7—8. However, on heavy or poorly aerated soil they grow poorly. Rhododendrons have certain light requirements but do not tolerate scorching sun; in summer and autumn they should be shaded from strong sun by deciduous trees or a shade frame, and the ground should be sprayed with water regularly.

Rhododendrons generally send out new shoots in spring and autumn, mainly in spring. The most suitable growth temperature is 15—20 degrees. When the temperature exceeds 30 degrees or falls below 5 degrees, growth stops. There is a brief dormant period in winter, after which the flower buds gradually swell as the temperature rises. Generally, plants grown in the open flower from March to May, while in high-altitude areas they flower as late as July to August. In the north, when grown in a greenhouse, they can flower in January to February.

Rhododendrons tolerate pruning, and latent buds sprout very readily once stimulated, which can be used to control the plant's shape and rejuvenate the plant. Pruning is generally carried out before May; the new shoots produced can all form flower buds in the same year, while pruning too late affects flowering. New shoots that emerge around the Beginning of Autumn can still lignify. If new shoots form too late, they are prone to frost damage in winter.

Rhododendron growth habits and the effects and benefits of rhododendrons

When rhododendrons are in full bloom, it is exactly when the cuckoo bird calls; the ancients left behind many poems and beautiful, moving legends, and there is even the custom of a flower festival. Rhododendrons are mostly shrubs or small trees, and because of different ecological environments they have their own habits and forms. The smallest plants are only a few centimeters tall, cushion-shaped and growing close to the ground. The largest reach several zhang in height, standing tall and magnificent. So, what effects do rhododendrons have? Let's find out together.

I. Rhododendron growth habits

The habits of rhododendrons range from evergreen to deciduous, and from low ground-covering plants to tall trees. The earliest cultivated for garden ornament in the mid-17th century was the densely hairy alpine rhododendron (Rhirsutum), which can reach 1 meter (3 chi) in height. Others range from mat-like dwarf species only 10 cm (4 cun) tall to trees over 12 m tall, the former including the prostrate rhododendron (Rprostratum) native to Yunnan, China, and the latter including the tree rhododendron, the hard-thorned rhododendron (Rbarbatum) and the giant rhododendron (Rgiganteum) native to Asia. Except for the azalea types, the leaves are all thick, leathery and evergreen; the flowers are usually tubular to funnel-shaped, with greatly varying colors, including white, yellow, pink, crimson, purple and blue.

China is the distribution center of rhododendrons, with about 530 species, found in all provinces and regions except ** and Ningxia. Southeastern Tibet, southwestern Sichuan and northwestern Yunnan are the most concentrated places of origin, each with more than a hundred species, and Yunnan alone accounts for more than half of the country's rhododendron varieties. Many countries around the world have introduced species from here.

Rhododendron is a large genus, with about 900 species worldwide, distributed in Europe, Asia and North America, with the most in Asia, 850 species, of which China has more than 530 species, accounting for 59% of the world total, especially concentrated in the Hengduan Mountains area of the three provinces and regions of Yunnan, Tibet and Sichuan, which is the birthplace and distribution center of the world's rhododendrons. In the Himalayas, Bhutan, Sikkim, Nepal, Myanmar and northern India also have relatively many species, while Japan, Korea, Soviet Siberia and the Caucasus have only a few species.

II. The effects of rhododendrons

Rhododendron is also known as yingshanhong and has the reputation of being the beauty of flowers. Its flowers, roots, stems and leaves can all be used medicinally; the flowers are gathered in early spring, and the leaves and roots in autumn and winter. Rhododendron tastes sour and sweet and is warm in nature. It is generally considered relatively mild in medicinal action, with the effects of harmonizing the blood, regulating menstruation and dispelling wind-dampness. It is suitable for irregular menstruation, amenorrhea, abnormal uterine bleeding, traumatic injuries, rheumatic pain, hematemesis, epistaxis and so on. Clinical application shows that rhododendron flowers, leaves and roots all have hemostatic effects, and can also relieve cough, resolve phlegm and calm asthma, and are mostly used for acute and chronic bronchitis, cough with copious phlegm and other respiratory conditions.

[For cough with copious phlegm] 30 to 40 grams of rhododendron flowers, decocted in water alone, can be used for chronic bronchitis and cough with copious phlegm; purple-flowered rhododendron tablets may also be used, 5 tablets each time, 3 times a day, taken with warm boiled water. At present, capsules and cough-and-asthma oral liquids made from manshanhong (of the genus Rhododendron in the family Ericaceae) have become common medicines for bronchitis and can be chosen under a doctor's guidance.

[For phlegm-fluid cough and asthma] 10 grams of rhododendron flowers, 3 grams of yuanhua, 10 grams of kuandonghua. Decoct in water. This formula has good effects in relieving cough and resolving phlegm, calming asthma and dispelling fluid retention. It is suitable for persistent cough, copious phlegm, fluid retention in the chest and hypochondrium, cough and asthma with inability to lie flat, chest tightness and shortness of breath, facial edema, purple lips and so on.

[For hemoptysis] Use 10 grams of rhododendron flowers, 30 grams of xianhecao, 10 grams of baiji, 5 grams of licorice, decoct in water, 1 dose per day.

[For epistaxis] 15 to 30 grams of rhododendron flowers, decocted in water. It has a good effect on nosebleeds.

[For irregular menstruation] For irregular menstruation with abdominal pain during menstruation, use 10 grams of rhododendron flowers, 5 grams of Chinese rose flowers, 20 grams of yimucao, decoct in water, 1 dose per day. For amenorrhea with emaciation, use 60 grams of yingshanhong, decoct in water, and stop once the condition improves.

[For skin diseases] Decoct fresh rhododendron leaves in water for bathing, which can treat urticaria. 60 grams of rhododendron flowers and 30 grams of tung tree flowers, roasted dry and ground into powder, mixed with tung oil and applied to the affected area (shave the head first, then apply the medicine), can treat scalp ringworm (favus).

Note that the rhododendron plants generally used medicinally are pink; the plants and flowers of yellow rhododendrons contain toxins, and accidental ingestion causes poisoning; the flowers of white rhododendrons contain tetracyclic diterpenoid toxins, and poisoning causes vomiting, difficulty breathing, numbness of the limbs and so on. None of these should be eaten or used medicinally.

III. The uses of rhododendrons

1. It has certain medicinal value. Rhododendron is sweet with a slight bitterness, neutral and delicately fragrant, and has certain medicinal value in medicine. Among the people, rhododendron is often stewed with pig trotters; it can dispel wind-dampness, regulate menstruation and harmonize the blood, calm the mind and remove dryness, and can treat abnormal vaginal discharge in women, while long-term use has whitening and spot-removing effects. As a very famous Chinese herbal medicine, the leaves and flowers of rhododendron can treat urticaria and have marked effects in relieving cough and resolving phlegm and treating acute and chronic bronchitis. Every part of the rhododendron is very useful; its flowers, leaves and roots can all be used medicinally, and it is sour in taste and neutral in nature, able to invigorate the blood, stop bleeding and dispel wind-dampness. It has a marked effect on irregular menstruation; generally 10 grams of rhododendron flowers, 5 grams of Chinese rose flowers and 20 grams of yimucao can be decocted in water.

2. It has other uses. Rhododendrons have abundant flowers and lush leaves, are gorgeous and varied, have strong sprouting ability and tolerate pruning, making them excellent bonsai material. In gardens, they are best planted in clumps or masses along forest edges, by streams, beside ponds and near rocks, and can also be scattered under open woodland. Rhododendrons are also good material for flowering hedges, and mao azaleas can also be pruned and trained into various forms. Some can also be eaten; the flowers of yingshanhong are sour and non-toxic and can be eaten raw; the flowers of dabai rhododendron and cubing rhododendron are still excellent vegetables for the people of central Yunnan; soaking and composting the branches, leaves and flowers of yangzhizhu can make an insecticidal pesticide. Moreover, the bark and leaves of some species are rich in tannins and can be used to extract tannin extract. In addition, the wood and root burls of rhododendrons are fine-textured and tough and can be made into bowls, chopsticks, basins, alms bowls, pipes, root carvings and other daily-use crafts and artworks.

As an outstanding ornamental flower with extremely high ornamental value, the rhododendron can have so many uses, which is also very rare; friends who like it may as well grow a pot.

How to cultivate rhododendrons and how to propagate them

The rhododendron is a herbaceous plant of the Asteraceae family, itself only a little over half a meter tall, with feathery green leaves. The rhododendron surrounded by green leaves is very beautiful, elegant and distinctive with a special charm. Below, we share the propagation methods of rhododendrons. Propagation methods of rhododendrons

I. What is a rhododendron

The rhododendron is one of China's ten famous flowers, with very many species and bright, beautiful colors. Rhododendrons are deeply loved by everyone, because of their high ornamental value and because they can adorn courtyards, so they have long had the reputation of being the beauty among flowers.

II. Propagation methods of rhododendrons

When propagating rhododendrons, pay attention to their growth habits. The rhododendron is a plant that likes coolness but avoids summer heat, so be sure to provide a certain degree of shading for rhododendrons, and it is best to know how to avoid scorching direct sunlight. Rhododendrons do not like dry soil, so prepare a moist soil living environment for them. Rhododendrons have relatively high requirements for acidic soil, so they must not be planted on saline-alkali land. Rhododendrons like lighter soil and must not be planted on heavy soil. Next is to rely on good drainage performance and not cause waterlogging in the soil.

III. How to grow rhododendrons——site

Rhododendrons can be planted indoors or outdoors in the open air. Planting rhododendrons requires a drainage slope, and if planted in flower pots, a partition plate needs to be installed.