How to Grow and Care for Rhododendron pulchrum

Rhododendron pulchrum, also known as the beautiful azalea, is an evergreen or semi-evergreen shrub in the family Ericaceae, genus Rhododendron. When planted in masses, it blooms in a splendid display of myriad colors, adding a natural landscape effect to gardens. It can also be planted in clusters beside rocks, by pond edges and along lawn borders to enhance the garden atmosphere. Grown in pots and placed in hotels, homes and public places, it is dazzling to the eye. Let us take a look at how to grow Rhododendron pulchrum!

Growing Habits of Rhododendron pulchrum

Rhododendron pulchrum is widely cultivated throughout China, and wild Rhododendron pulchrum grows in the Jiuling Mountain area of northwestern Jiangxi Province. It prefers a cool, moist and sunny environment. It is cold-hardy, heat-sensitive and tolerates partial shade, but not prolonged intense direct sun. The optimum growing temperature is 15-28°C, and in winter it can withstand low temperatures of -8°C. The ideal soil is a fertile, loose, well-drained acidic sandy loam.

Propagation Methods of Rhododendron pulchrum

1. Cuttings: Propagate Rhododendron pulchrum by cuttings during the plum rain season. Select semi-mature young shoots 12-15 cm long, remove the 2-3 leaves at the base, keep the leaves at the tip and cut them in half. Treat the cuttings with a 0.8% indolebutyric acid solution for 2-3 seconds, insert them into a sand bed, and keep the room temperature at 15-18°C. Roots form 50-60 days after insertion.

2. Layering: Propagate Rhododendron pulchrum by layering in April-May, using the air layering method. Select a 2-3 year old mature branch, make a ring bark cut 2 cm wide at 20-30 cm from the branch tip, and wrap it with leaf mold and plastic film. It heals and roots in 4-5 months; cut it off in autumn and pot it up.

3. Sowing: Sow Rhododendron pulchrum seeds in April, using indoor pot sowing. The optimum germination temperature is 22-24°C; germination occurs 10-15 days after sowing, but the seedlings grow slowly.

How to Grow Rhododendron pulchrum

1. Potting soil: Rhododendron pulchrum prefers acidic soil and requires a loose, well-drained medium rich in humus. Take 4 parts leaf mold, 2 parts old potting soil, and 1 part each of sandy soil, burnt soil and sawdust, add an appropriate amount of cake fertilizer, mix well, and compost for half a month before use.

2. Potting up: When potting up Rhododendron pulchrum, keep plenty of the original soil around the roots and damage the roots as little as possible; shorten excessively long roots appropriately, and prune the upper branches of larger plants. First cover the drainage hole at the bottom of the pot with overlapping broken tile pieces, spread a layer of coarse-grained soil as a drainage layer, put part of the growing medium in the center, then place the plant in the pot, hold it upright, add soil and press it firm. The planting depth should match the original depth at which the seedling was lifted, then water thoroughly.

3. Watering: Rhododendron pulchrum fears both drought and waterlogging. From the end of November to mid-to-early February of the following year, most open-ground potted beautiful azaleas are dormant or semi-dormant, so water moderately according to whether the potting soil is dry or moist. In late February, when the temperature rises and flower buds and leaf buds begin to swell, increase the watering frequency appropriately. March to June is the period of vigorous new shoot growth, when water demand increases, so increase the watering frequency as needed. July to September is hot, so water every day. After October, the amount of watering can be reduced.

4. Fertilizing: Rhododendron pulchrum does not like heavy fertilizer; apply dilute fertilizer frequently. For base fertilizer, use long-acting fertilizers such as cake fertilizer, bone meal and dried rotted manure and other organic fertilizers, buried in the potting soil when potting up, repotting or in winter. For top dressing, use quick-acting fertilizers such as organic human manure or nitrogen, phosphorus and potassium chemical fertilizers. From the Beginning of Spring to before flowering, apply phosphorus and potassium fertilizer 1-2 times a month, and stop fertilizing during flowering. After the weather turns cool in autumn, apply a liquid fertilizer based mainly on phosphorus 1-2 times, and stop top dressing after winter sets in.

5. Pruning: During the growing season, Rhododendron pulchrum must be pinched back and pruned, removing dead branches and sprouting suckers, which helps the plant form a balanced shape. For ground planting, choose an acidic soil in a high, dry site with abundant sunlight and a deep soil layer. Apply fertilizer once each before and after flowering every year, cut out overly dense inner branches, shorten leggy branches, and remove dead and diseased branches to ensure that Rhododendron pulchrum can grow vigorously.