Azalea Care Methods and Precautions During the Bud Stage

Azaleas are perennial woody plants of the genus Rhododendron in the family Ericaceae. In their natural state they grow upright, and under cultivation they can be pruned into various shapes. The bud stage refers to the period from the appearance of buds until most of the flowers have opened, generally 90 to 120 days (the length of this period is greatly affected by the care temperature). The key care points during the bud stage (for production) are:

During the bud stage, azaleas should be kept in a moderate-temperature greenhouse, with a night temperature of 10°C to 15°C and a day temperature of 18°C to 25°C. When forcing bloom, the temperature should be somewhat higher (day temperature 20°C to 30°C, night temperature 15°C to 18°C), and after flowering the temperature should be somewhat lower (day temperature 10°C to 15°C, night temperature 5°C to 10°C). To ensure uniform flowering, plants with buds at different stages of development should be kept under different temperature conditions. Temperature changes in the care environment should not be too drastic, and cold air should be kept from blowing directly on the azalea plants.

Azaleas must be kept under semi-shaded conditions (plastic film can provide shading). In the early stage of bud appearance, light should be appropriately increased; in the late stage of bud swelling, light should be reduced. Shading can delay flowering and extend the flowering period, but the flower color will appear slightly duller, which should be noted.

Air humidity should preferably reach 70% to 80%. The ground should be kept moist, and steam humidification should be used when necessary. When misting to increase humidity, take care to prevent alkaline deposits from forming on the leaves. The watering interval depends on how dry or moist the potting soil is: small pots should be watered once every 2 to 3 days, and large pots once every 5 to 7 days. Water should be poured directly into the pot, not sprayed over the canopy. It is best to use water that has been stored so its temperature is close to room temperature. For plants whose leaves have already wilted from drought and water loss, use the soaking method to let the potting soil absorb water thoroughly, and place them in a cool spot to recover.

When the temperature is high each day, open the vents to ventilate and exchange the air, keeping the air clean and ensuring the azaleas grow vigorously and the leaves stay clean. When it is windy, be sure to close the vents to prevent dust and debris from entering the room and settling on the leaves.

After the azaleas show buds, fertilizer should be applied 2 to 3 times, mainly phosphorus and potassium fertilizers. Foliar spraying with 1% to 2% potassium dihydrogen phosphate (once a week) gives good results. Fertilization can be stopped after the buds swell. Note that fertilizers with a pungent odor must not be used.

Azaleas have relatively few pests and diseases during the bud stage. Generally, a fungicide can be sprayed once every 7 to 10 days to prevent disease. To reduce nutrient consumption and the breeding of disease, flowers that open early should be removed promptly.

When the flowers begin to show color, the azaleas can be moved into more decorative pots (such as porcelain pots, purple clay pots, or plastic pots). When repotting, the original root ball must not be broken; use a pot slightly larger than the original one, add nutrient-rich organic soil around the sides, and protect the flowers and leaves well.

Once the flowering period begins, lower the temperature, reduce light, and lower air humidity to extend the flowering period.