Cultivation Techniques and Management Methods for Belgian Azaleas

Belgian azalea, also known as Western azalea. It produces abundant flowers, has a long flowering period and grows quickly, and is a valuable ornamental flower introduced into China from the Netherlands and Belgium in recent years. It belongs to the Ericaceae family and is an evergreen small shrub.

I. Flower habits: Belgian azalea is an acid-loving flower with well-developed, fine fibrous roots. When planting, loose soil with good permeability should be chosen, with humus soil from under forest trees being the best. During growth it prefers conditions of high temperature and high humidity.

II. Cutting propagation: Belgian azalea has a long growth period and can be propagated by cuttings throughout the year, with spring and autumn generally being the best.

1. Making the bed: The bed height is 15 cm, the width is 1 m and the length is 10 m. Clear away weeds, roots and stones, break up the soil to form the bed frame, then spread a 2 cm thick layer of humus soil and compact it, then spread a layer of sifted yellow soil with a particle size of 0.2 mm to 0.3 mm on top, with a thickness of between 1.5 cm and 2 cm, and water it thoroughly before use.

2. Collecting cuttings: Collect semi-lignified current-year branches from robust mother plants as cuttings. For excessively long branches, the lower node can be removed.

3. Cutting: The cutting branches should be 6 cm to 8 cm long, retaining 3 to 4 leaves at the top. The insertion depth is 0.5 cm to 1 cm; too deep easily causes water accumulation and rot at the base of the cutting, affecting rooting; too shallow easily causes water loss and wilting. A plant-to-row spacing of 2 cm x 3 cm is sufficient.

4. Management after cutting: After cutting, water thoroughly, seal and cover with plastic film, and cover with a layer of shade netting on top (use two layers when cutting in summer) to maintain conditions of high temperature and high humidity inside the bed. Every 3 to 5 days, press the seedbed by hand to check the moisture conditions. If the humidity is insufficient, water at the appropriate time and seal the cover again immediately after watering. Generally, new roots can grow in 20 to 30 days, and after 45 to 50 days the seedlings can be transplanted for planting. According to experiments, with the above technical measures for cutting, the survival rate of the cuttings is around 90%.

III. Cultivation management: The cultivation techniques for Belgian azalea flowers are relatively complex, with strict requirements for fertilizer and water, and different management measures for each season. Generally, it is necessary to avoid water in the rainy season, provide shade in summer and protect against cold in winter, while artificially controlling the flowering period accurately.

1. Soil disinfection: In addition to requiring loose, acidic soil, Belgian azalea has strict requirements for soil environmental conditions. When preparing the field seedbed, use 1.5 jin of carbofuran and a potassium permanganate solution diluted 1000 times per mu for soil disinfection treatment, which can control cutworms, crickets, mole crickets and diseases; for potting soil, steam fumigation or potassium permanganate disinfection can be used before planting, so that the soil meets the use requirements of being clean, hygienic and free of pests and diseases.

2. Fertilizer and water management: Belgian azalea grows quickly, has many branches and leaves, and has a long growth period, so it needs sufficient fertilizer and water. Because its fibrous roots are fine, fertilization should be mainly foliar fertilizer, supplemented by peanut bran as base fertilizer. At present, the main products on the market include Yemianbao, Lüfenwei I, II, III, Aiduoshou, Gaochangling and others, which can be used alternately. Apply thin fertilizer frequently; generally fertilize once a week and spray fungicide twice a month, combining sterilization when applying foliar fertilizer. At the same time, depending on the greenness of the leaves, spray 5% ferrous sulfate to supplement acid. Water conditions are also very important for its growth. Except on rainy days, generally field-grown seedlings are watered once every two days and potted seedlings once a day. When displayed indoors, do not water unless dry, and water thoroughly when watering.

3. Shading: Belgian azalea is a semi-shade flower. When planted outdoors, shading facilities must be provided in summer, with a shading level of about 75%. If a balcony planting receives western sun, it can be moved to a shaded place in the afternoon. Rain-shelter management should be carried out during the rainy season; prolonged rain will cause water accumulation at the roots, leading to leaf drop and even root rot and death of the plant.

4. Reasonable pruning: As mother trees, they can be pruned multiple times a year for cuttings. For ornamental planting, prune twice a year. The first time is after the Spring Festival when flowering is finished, cutting off all flower stalks and reasonably shaping and pruning; the second time is before the end of the sixth lunar month each year, cutting off all terminal buds, with each branch pruned neatly and none missed, combined with shaping; at ordinary times, prune irregular flower buds. This achieves the ideal pruning effect of luxuriant branches and leaves, a reasonable tree shape and uniform flower buds.

5. Cold protection: Do a good job of cold protection in winter; for open-air planting, cover with plastic film at night.

6. Pest and disease control: Common pests and diseases of Belgian azalea flowers include cutworms, aphids, wood-boring insects and leaf-eating moths, which can be controlled with drugs such as carbofuran, methamidophos and dimethoate.