How to Grow Four-Season Azaleas? Detailed Guide to the Latest Cultivation Methods
The four-season azalea is a variety of the evergreen or semi-evergreen shrub azalea of the genus Rhododendron in the family Ericaceae, also known as the Belgian azalea. Its petals are narrow and long, the filaments are red, and the anthers are golden yellow. It blooms continuously throughout the four seasons and is an excellent flowering ornamental plant. It can be planted in groups or grown in pots for viewing. Below, let us take a look together at the cultivation methods and precautions for four-season azaleas!
Propagation Techniques for Four-Season Azaleas
Four-season azaleas are mainly propagated by cuttings. In spring and summer, select two-year-old branches with short internodes and thick, robust growth, cut them to about 5 cm for insertion, and keep 3 to 5 leaves at the top. Sand and perlite are good cutting media. Provide shade and spray water frequently. After cutting, roots form in about 1 month, and the plants can be potted in 3 months. The survival rate reaches over 90%. The potting soil should be an acidic culture soil of the same period, permeable, and rich in organic matter, with a pH value of 5 to 6. It is commonly made by mixing leaf mold, moss, and mountain soil in a ratio of 2:1:7.
Cultivation Methods for Four-Season Azaleas
1. Watering: Azalea roots are very fine and have relatively poor absorption capacity, and water must be absorbed through the roots before it can reach the plant body. Therefore, except during the winter dormant period, azaleas should be watered frequently to keep them moist. Especially during the growth period after March each year, the flowering period, and the high-temperature period from July to September, the frequency of watering should be increased, preferably ensuring watering about twice a day. In autumn and winter, watering can be appropriately reduced. It should be noted that tap water used for watering flowers is best stored in a container for one to two days before being used to water the flowers.
2. Light: During the cultivation of azaleas, sufficient light should be ensured at all times, because only with sufficient light can the flowers bloom well. Of course, in hot summer, they should not be put out for direct sun exposure. Instead, shading work should be strengthened to prevent sun damage. In addition, during the flowering season, appropriate protection should also be provided, and a shade net can be used for protection. They also must not be exposed to direct sun during the flowering period.
3. Fertilizing: Proper fertilizing can make azaleas grow more robustly and rapidly during cultivation. As with most indoor flower cultivation, the fertilizing principle for azaleas is also to apply thin fertilizer frequently, that is, apply a little less at a time but apply it more times. When old leaves turn green, during the flowering period, and after flowering, appropriately fertilize two to three times. During hot, high-temperature weather, fertilizer must not be applied. For azalea cultivation and fertilizing, materials such as grass juice water, fishy water, and rapeseed cake can be used.
4. Placement: When large potted four-season azaleas bloom, they are colorful and the whole tree is full of flowers. They can be placed at the entrances of hotels, shops, or government offices, appearing extremely noble, elegant, and magnificent, with an ornamental effect superior to that of sago palms and similar plants. Medium-sized four-season azaleas are dazzling and eye-catching when in bloom and can be placed on indoor office desks or coffee tables. If used to decorate a meeting room, they have an invigorating effect, as if entering a place where spring lasts all year. Small four-season azaleas are generally not used for viewing and should preferably be cultivated in a concentrated way, ideally in plastic greenhouses. After they grow into medium-sized plants, they can be sold or used for viewing.
Precautions for Four-Season Azaleas
1. Pest control: Spider mites are relatively common on four-season azaleas and are caused by dry heat. Spider mites suck leaf sap, causing the whole plant to gradually turn yellow and wilt. In daily care, regularly check the undersides of leaves. If small reddish-brown spots resembling “mites” are found, these are spider mites, along with webbing. At this time, the four-season azalea should first be isolated, and a relatively strong stream of water should be used through a rubber hose to wash the infested leaf undersides. After it dries slightly, more than ten fresh oleander leaves can be chopped, added to five cigarette butts (taking only the tobacco, about the amount of one cigarette) and one chopped raw red chili pepper, soaked in 500 ml of water for twenty-four hours, then sprayed on the stems and leaves every three days, and placed in a ventilated place to dry, for three consecutive sprays. In daily care, keep it moist and maintain air circulation.
2. Yellowing leaves: Yellowing leaves on four-season azaleas are a physiological disease caused by a lack of iron, trace elements, and soil that is too alkaline. All azaleas like slightly acidic soil, which should be loose and well-draining, and must not be compacted. In severe cases, the soil should be replaced with a mixture of equal parts packaged “potting soil”, peat soil, and black soil (leaf mold). In mild cases, several rusty iron nails can be buried in the soil.
3. Early withering of flower buds: The leaf tips and edges of four-season azaleas will also wrinkle, curl, and turn yellow-brown at the same time. This is caused by applying concentrated fertilizer when flower buds are present, or by heat and poor ventilation, or by excessive dryness, or by compacted soil. When buds appear, fertilizing should stop, and the plant should be placed in a cool, airy place with only sufficient scattered light, avoiding harsh sun. The potting soil should be kept appropriately moist and not dry, and the soil should be replaced once every year after the flowers fade. Affected buds and leaves should be removed.
4. Brown spots on leaf edges: Brown spots on leaf edges are the main disease of four-season azaleas, called brown spot disease, caused by excessive moisture, lack of light, and heat with poor ventilation. Diseased leaves should be removed, and a 600-times dilution of “Daconil” should be sprayed once a week for three consecutive sprays.