What are the cultivation methods and precautions for the four-season camellia?
The four-season camellia is currently one of the most precious camellia varieties in the world that blooms in all four seasons, with only 840 plants remaining in the wild worldwide. It is also known as the rhododendron red camellia, four-season rhododendron camellia, etc. Its flowers are large, and when in full bloom they are bright and fiery red, much like rhododendron flowers. Its leaves are dark green and glossy, with the elegance of rhododendron leaves. It grows vigorously and blooms year-round. Let's take a look below at the cultivation methods and precautions for the four-season camellia!
Growth habits of the four-season camellia
The four-season camellia grows beside small streams in dense forests with few people around. The annual average temperature in its growing area is 22.1°C, the highest temperature is 38.4°C, the lowest temperature is -1.8°C, the average temperature in July is 28.2°C, and the average temperature in January is 14.3°C. The annual sunshine hours are 1200 hours, and the frost-free period is 350 days. The annual average rainfall is 3428.9 mm, and the relative humidity is 85%. The soil parent material is granite, red soil, with a soil pH of 5.5-6. It is generally distributed in the lower layer of the forest canopy. It is a semi-heliophilous tree species and is relatively shade-tolerant.
Propagation methods for the four-season camellia
1. Cuttage: Mostly carried out in May to June. It is best to choose robust current-year branches as cuttings, cut them into 10-12 cm lengths, keep 2-3 leaves at the upper part, and remove the lower leaves. Insert them into a plain sand seedbed or flowerpot. River sand or loose mountain soil can both be used as potting soil. After insertion, water thoroughly, then spray water appropriately afterward, keep the soil moist, and provide shade. Roots can form in about 60-70 days.
2. Air layering: Mostly carried out in April to May. The method is to select branches from the previous year, perform ring barking at the layering site with a ring width of 0.5 cm, wrap the ring-barked part with plastic film of appropriate size, with a wrapping length of 10-15 cm. First tie the lower opening tightly, fill it with moist cultivation soil, keep the soil moist often, then tie the upper opening tightly. After roots develop, it can be cut off and planted separately.
Cultivation methods for the four-season camellia
1. Soil: The four-season camellia has high soil requirements. Generally, its soil is relatively rich in humus, with a pH between 5 and 6.5, slightly acidic. Its optimal soil mix is 50% mountain soil, 40% sawdust or edible mushroom residue, and 10% cake fertilizer powder or livestock manure and phosphate fertilizer powder.
2. Light: The four-season camellia avoids strong light, so attention must be paid to sunlight when planting. In spring and autumn, sufficient light is required, but in summer it must avoid direct sunlight. If exposed to strong light for too long, it can easily die.
3. Temperature: The four-season camellia is neither cold-tolerant nor heat-tolerant. Its most suitable temperature is 18-25°C, so the ambient temperature must not be too high or too low, otherwise both will affect its growth. In winter, the indoor temperature must be above 3°C. If it is below 0°C, it will suffer frost damage.
4. Watering: The four-season camellia likes a moist environment. It cannot be too dry, too wet, or alternating between dry and wet. In spring, it can be watered more. In summer, water twice a day, in the morning and evening. In autumn, do the same as in spring. In winter, it is best to water before and after the plant.
5. Fertilizing: The four-season camellia prefers fertilizer, but there is also a limit to fertilizing. It must not be too much. Generally, fertilize about 3 times in the nearly half year after flowering, and once in winter is enough. In order to make the flowers more beautiful, it is best to add more phosphate fertilizer to the fertilizer.
6. Pruning: Pruning the four-season camellia is very important. Generally, branches that affect the tree shape and diseased or weak branches are cut off, and flower buds are also arranged. Once the flower buds are too dense, they must also be thinned out. After the flowers wither, they should also be picked off in time, which can reduce nutrient consumption.
7. Repotting: The four-season camellia generally needs repotting once every two years. Changing to a larger pot is beneficial to its growth. The best time for repotting is April. Do not remove all the old soil, and also add a small amount of base fertilizer, then water.
8. Pests and diseases: The four-season camellia is very prone to illness. The common ones are mainly black mold and anthracnose. In this case, it is only necessary to spray 0.5-degree Bordeaux mixture. The main pest is the tea shoot borer. In this case, it is enough to cut off the infested shoots.
Precautions for the four-season camellia
1. The four-season camellia should not be heavily pruned. The development time of flowers, leaves, and buds is relatively long, and the crown forms relatively evenly. Basically, no special pruning is needed. It is enough to cut off diseased and pest-infested branches, overly dense branches, and weak branches, and shorten leggy branches.
2. The four-season camellia is a multi-flowered tree species, especially on weak-growing plants. If flower buds are dense, they will consume too many nutrients, which is unfavorable to plant growth, so bud thinning is an important part of cultivation management.
3. The flowering period of the four-season camellia is relatively long, with the entire flowering period lasting up to one year, so promptly picking off flowers that are near withering is greatly beneficial for reducing nutrient consumption and strengthening the tree's vigor.
4. In spring and the plum rain period, the four-season camellia should be given sufficient sunlight, otherwise the branches will develop thinly and weakly, and it is easily harmed by sooty mold and scale insects or covered with moss, leading to dead branches, aging, or death.
5. In the high-temperature seasons of summer and autumn, the four-season camellia should be shaded and cooled in time. If the winter temperature drops below 0°C, it will cause flower buds to fall or flower cores to freeze. Potted seedlings overwintering indoors should preferably be kept at around 3-4°C.
6. The amount of fertilizer for the four-season camellia should be controlled by applying more to strong seedlings and less or none to weak seedlings. For seedlings that are too weak, replacing the potting soil instead of fertilizing also has a very good effect.
7. The four-season camellia has extremely high requirements for air circulation and is best grown in a gentle breeze, but it is afraid of northwest winds and strong winds, because northwest winds and strong winds can easily cause water to evaporate too quickly and upset the balance of supply and demand, which is not conducive to growth.