When is the latest blooming time for the rhododendron (Rhododendron pulchrum)?
The rhododendron (Rhododendron pulchrum) is a type of azalea, suitable for planting in a sunny, cool and humid environment. When planted in large patches, the rhododendron blooms in a riot of brilliant colors, and it is mostly used to create natural garden landscapes. Some people also like to place rhododendrons indoors to enhance the indoor atmosphere, and during festivals they are also often used to decorate public places for a festive effect. Now let us take a look at when the rhododendron blooms!
When does the rhododendron bloom?
The blooming time of the rhododendron varies because the climatic conditions differ from place to place. Generally, the rhododendron blooms in summer and autumn. Some rhododendrons grown at home by enthusiasts sometimes bloom in November. In short, the blooming time of the rhododendron varies according to climate, living environment and care during cultivation. The flowers of the rhododendron are much admired for their distinctive shape and beautiful color. 2 to 3 flowers emerge from the top buds together with the new shoots; the corolla is rose-red to bright red, with a deep red blotch on the upper petal, wheel-shaped, about 4.5 to 7 cm in diameter, with 5 stamens, yellow anthers, small ovate sepals, light green, with fine hairs.
Growth habits of the rhododendron
The rhododendron is widely cultivated throughout China, and wild rhododendrons grow in the Jiuling Mountain area of northwestern Jiangxi Province. It likes a cool, humid and sunny environment. It is cold-tolerant, afraid of heat, tolerant of partial shade, and not tolerant of long periods of intense direct sunlight. The optimum growth temperature is 15 to 28°C, and in winter it can withstand low temperatures of -8°C. The soil should preferably be fertile, loose, well-drained acidic sandy loam.
How to grow the rhododendron
1. Potting soil: The rhododendron likes acidic soil and requires loose, well-drained soil rich in humus. Take 4 parts humus soil, 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: When potting the rhododendron, the seedlings usually carry their original soil, and the roots should be damaged as little as possible. Overly long roots should be shortened appropriately, and larger plants should have their upper branches pruned. 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, then fill part of the growing medium in the center, place the plant into the pot and straighten it, add soil and press it firm. The planting depth should be equivalent to the depth at which the seedling was originally lifted from the soil, then water thoroughly.
3. Watering: The rhododendron is afraid of both drought and waterlogging. From the end of November to the first and middle ten days of February of the following year, most open-air potted Rhododendron pulchrum are in a dormant or semi-dormant state, so water appropriately according to the moisture condition of the potting soil. In late February, when the temperature rises and the flower buds and leaf buds begin to sprout, appropriately increase the frequency of watering. From March to June, the new shoots grow vigorously and the water requirement increases, so the frequency of watering should be increased accordingly. From July to September, the temperature is high, so water every day. After October, the amount of watering can be reduced.
4. Fertilizing: The rhododendron does not like heavy fertilizer; apply dilute fertilizer frequently. Use long-acting fertilizers as base fertilizer, such as cake fertilizer, bone meal and dried aged manure and other organic fertilizers, buried into the potting soil when potting, repotting or in winter. Use quick-acting fertilizers as top dressing, such as organic human manure or nitrogen, phosphorus and potassium chemical fertilizers. From the beginning of spring to before blooming, apply phosphorus and potassium fertilizer 1 to 2 times a month, and stop fertilizing when blooming. After the weather turns cool in autumn, apply liquid fertilizer mainly of phosphorus fertilizer 1 to 2 times, and stop top dressing after winter begins.
5. Pruning: During the growing period, the rhododendron must be pinched back and pruned, removing dead branches and adventitious shoots, which is beneficial for the balanced development of the tree shape. For ground planting, choose acidic soil in a high, dry location with sufficient sunlight and deep soil. Apply fertilizer once each before and after blooming every year, cut out overly dense inner branches, shorten leggy branches, and cut off dead and diseased branches to ensure that the rhododendron can grow vigorously.