Azalea plant: growing azalea and treatment


Azaleas plants belong to the Ericaceae (hearth) family. They grow in cool mountain forests of the northern hemisphere. Botanists gave the name “azalea” to the subkinds of rhododendrons that are adapted for growing in house and in greenhouses. In natural conditions the azalea plant is an evergreen and deciduous bush or small trees.  Nowadays you can find azaleas for sale in many florist shops.
House azalea plant is very decorative and favoured by many floriculturists. The thing is not only that the flower is very beautiful, but that it also blossoms in winter when the most house plants are at rest and do not blossom, and we want bright colours – so azalea flower is willingly purchased and is often presented with instead of a holiday bouquet. In Japan they used to growing azalea shrub in a special way. Nowadays azalea bonsai is rather popular worldwide.


Two types of azalea plant are the most common – azalea Indica, or Indian azalea (rhododendron simsii) and azalea Japonica, or Japanese azalea (rhododendron obtusum).
Azalea Indica – rhododendron simsii is a small evergreen bush up to 50 cm high. Young sprouts are almost always covered with flat, chestnut-brownish bristly fuzz. The leaves are small (3-5 cm long), leathery, the upper surface is dark-green, the underside is light-green, covered with reddish fuzz. The leaves are short-stalked. The azalea flowers make up inflorescences, they can be double and single, wide funnel-shaped (3-5 cm in diameter), they open simultaneously. The Indian azalea’s colour can vary from white to bright red. Often azalea flower is two-coloured: white with pink centre and a border around the edge, and spotted.
Azalea Japonica appears rarely as a pot plant. It is also a short bush with small shiny leaves from 3 to 5 cm long. It usually blossoms with small (up to 3 cm in diameter) flowers. The flowers are funnel-shaped, of different coloring.
After blossoming in the premise, azalea Japonica can be bedded in the open soil. This kind of azalea bush is rather cold-resistant. It survives the frosts of 20 degrees, but growing azalea (rhododendron) in the open soil requires special knowledge that is not considered in this article.
Indoor azalea shrubs are also recognized by color. Common florists often call them like red azalea, pink azalea, white azalea or yellow azalea. In bonsai azalea is also called dwarf azaleas.



Like the majority of rhododendron azalea bushes are fastidious plants. That is why very often the azalea flower bought at the florist’s loses its leaves and dies after several weeks of blossoming, but if you create appropriate conditions it will blossom year after year.
Azalea flower likes coolness. The temperature should not be higher than +18 degrees and the optimal temperature for the azalea plant is 10-15 degrees above zero. In winter azalea plant can be kept in closed loggias while the temperature there is above zero (not less than +5). During this period (October-December) flower buds start to form. When the temperature decreases azalea plant should be taken inside, put on the north or west windows and protected from hot air of central heating. The desirable temperature in this period is 13-16 degrees above zero. Such temperature conditions stimulate blossoming, and if you decrease the temperature a bit during blossoming, it will extend the period of blossoming. In order to create such conditions floriculturists use some tricks. For example, they put ice along the edge of the pot, water the plant with melt cold water, spray it. If the room is too hot and dry the period of azalea’s blossoming shortens considerably and even the buds can fall.
Watering conditions are closely connected with temperature conditions. Azalea flower is a humid climate plant, so the soil must be constantly damp but not wet. At lower temperatures watering must be cut and the plant should not be sprayed, at higher temperatures – vice versa. If the soil is dry it should be moistened. To do this you are to put the pot with the plant in a container with water for not more than 3-4 hours and keep there until the earth lump is saturated with water. 2-3 days after this procedure you should resume regular watering. You should be especially careful about soil moisture in dry warm premises with central heating. Soil surface watering must be alternated with watering from underpan. In summer, when it is hot, azalea should be watered twice a day – in the morning and in the evening; and you should not forget to spray it.
The best water for house azalea is rainwater, melt-water or distilled water. If you water the plant with tap water, you should distill it or even boil. The plant should be sprayed with boiled water too. Azalea plant does not like hard water at all. Rarely (once a fortnight) house azalea can be watered with weak solution of citric acid (one teaspoonful for 2 liters of water). It will allow keeping the necessary acidity of soil. Another way to acidify soil is watering the plant with very weak solution (0.2%) of sulfuric acid once in 3-4 months. Acidifying watering must be made only after the soil is damped.
Taking care of azalea flower includes bright lighting, but direct sunrays can destroy azalea plant, its leaves begin to shrink, and buds to fall. You should find a proper place for azalea plant where it won’t be accessible for direct sunrays but the lighting will be sufficient.
When the azalea flowers stop blossoming treatment should be continued. First, all faded flowers should be removed together azalea1with pedicles. Brownish leaves must be removed, too. A month after blossoming finishes, when 3-4 pairs of leaves are formed on young sprouts, the tops of sprouts must be nipped. This procedure should be repeated three times a year. The sprouts are nipped last time before the buds start to form – in July or the beginning of August. Nipping is obligatory for azalea plant. It increases the blossoming intensity. If young sprouts appear near the buds which have just been formed, you should remove them.
After blossoming (in spring) weak and very long sprouts must be cut and the plants themselves should be transplanted. You should transplant adult azalea once in two years, and young plants (up to the age of three) – once a year. For transplantation wide flat pots are the best as azalea root system is horizontal and prefers the upper layer of soil which is well-aired and does not need loosening which can harm the plant’s roots.
The soil meant for azalea planting can be bought at the florist shop as it has a complicated composition. Though, if you have all the components, you can make the necessary earth mixture yourselves. The soil for azalea plant should consist of turf and deciduous earth with 1 part of hearth (Ericaceae) earth and a part of coniferous earth with some bank sand. There must be drainage in the bottom of the pot.
During the transplantation pay attention to the root collar (singulum) – it must not be covered with earth, otherwise the plant will die. Also you should try not to damage the roots while planting azalea, so try not to touch the earth clod around the roots, you just roll the plant over in the fresh soil, and if the pot is small, choose the bigger (for 2 cm) one.
In spring, when the danger of frosts is over, azalea plant can be taken outside, in the shadowy place. You can bed it in the garden, in the loggia or a balcony, where azalea plants can be kept until the first frosts come. Then they should be taken into well-lighted cool premises. People say that azaleas can stay outside “from cold to cold”. All this time the plant must be fertilized.


Azalea is usually reproduced by pruning, but this is not easy and very troublesome task, so buy azalea plant in the shop if you do not want these difficulties. If you still want to try pruning azalea, you should follow these rules:
- for cuttings young sprouts that are not entirely woody should be taken;
- cuttings should be from 10 to 15 cm long;
- the cutting is cut with the sharp knife or a blade above the leaf bud;
- leaves should be removed from the lower part of the cutting;
- the cutting should be put in the saucer with damp turf in the depth of near 5 cm;
- the earth around the cutting must be well pressed;
- the bedded cutting should be covered with a jar, polyethylene or put in a greenhouse;
- high humidity of air is necessary for rootage as well as the temperature of about +25 degrees;
- the cuttings must be regularly sprayed (up to 3 times a day) and aired so that they would not decay;
The cuttings strike roots for about half a year. After rooting azalea plants are transplanted in the permanent place and treated as it is described above.
Azalea can be reproduced also by layers, which you can try to implant. To do this, you can make a small cut on the side sprout over the leaf bud. One pair of leaves must be formed over such leaf bud. After this the layer is pinned to the earth with a wooden hook and covered with earth. Then you should wait until the plant strike roots, after which you should carefully separate the layer from the maternal plant in order not to damage the roots and transplant it in the pot.
Pruning azaleas should be done very carefully to get it propagated. You should remember it.



The guarantee of success in growing azalea is treatment, care and knowledge of the main rules. All azalea diseases are caused by breaking temperature conditions, improper watering, lack of light, unsuitable soil etc.
Wrinkled faded leaves, falling leaves and buds testify to insufficient soil moisture and air humidity, too high temperature or improper lighting. In this case you should water the plant more often, use the method of putting it in the container with water (see above), spray it, put the pot in the damp turf or on the tray with pebbles. Water should be added in the tray in the way that the bottom of the pot does not touch the water. Thus the necessary moisture will be created. You should be careful and keep the air temperature-moisture balance. When the temperature is higher watering must be intensified and it must be reduced when the temperature is low.
Direct sunrays are disastrous for azalea as well as the lack of lighting. Try to find an appropriate place for the flower.
Improperly chosen soil (azalea needs acidic soil), or watering with hard water result in yellow leaves, their falling and weak blossoming.
Azalea flowers are rarely attacked by pests. If the air is too warm and dry, and watering is insufficient, the plant can be the object of forceps’ and spiders’ attack.
Red spider is a tiny spider of red colour. It appears on the underside of the leaves and envelops them with thin white webs. It can be exterminated by spraying and washing the leaves, especially their underside, with water, weak tobacco solution with soap, dusting (in the open air, outside the rooms) with grind sulfur, or the plant can be treated with ready-made system insecticides. The treatment must be repeated several times until the pests are exterminated completely. In order to avoid affection with red spider the plant must be kept clean, often sprayed and far from the central heating.


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