Pruning is best in May. In order to maintain the beautiful appearance of azalea trees, we have to trim too many branches, buds and buds every year. When the rhododendron grows to a certain height, take off the terminal buds, control the height and sprout lateral branches. After enucleation, many lateral branches grow spirally. When the lateral branches grow to a certain height, then pick the core. Germinate secondary lateral branches.

Rhododendron has a strong ability to sprout new buds and grow long branches, so it should not be allowed to grow wantonly. It is necessary to prune, control and adjust reasonably and maintain a reasonable and beautiful tree shape. There are five pruning methods: core removal, bud stripping, bud wiping, branch thinning and short cutting. Generally, it is enough to wipe buds, twigs and cut short.

Bud wiping is to leave one or two buds on each branch, and the remaining buds should be wiped off, thus reducing the density of branches. Sparse branches-that is, pruned branches that are too dense, slender branches, overlapping branches, crossed branches, and sick branches. Short-cut-that is, cut short the overgrown branches and overgrown branches to make the tree beautiful and improve its ornamental value.

If it is shaped, it will be trimmed into various shapes according to the plant type. The usual shapes are umbrella and pagoda. In the former, the lower trunk should have multiple lateral branches, which can extend around. When modeling, use thick lead wire to make an umbrella-shaped skeleton on the basin, then evenly distribute the branches on it and tie them with plastic belts. Bloom will form a big ball. The latter should be pruned from the fixed stem, first shaping the bottom branches, then pruning upward step by step, and finally making the whole plant shape like a tower.

There are about 900 species of rhododendron, about 850 species in Asia, including about 53O species in China. Except Xinjiang, it is distributed in all provinces and regions of China, especially Yunnan, Tibet and Sichuan. Rhododendron species

There are many kinds and habits, but most of them are produced in high altitude areas, and they like cool and humid climate and hate hot and dry. It is required that the soil is rich in humus, loose, moist and acidic, and the pH value is between 5.5 and 6.5. Some species and horticultural varieties have strong adaptability, drought tolerance and barren tolerance, and can grow in the soil pH value of 7-8. But in the soil with poor viscosity or permeability, the growth is not good. Rhododendron has certain requirements for light, but it is not resistant to exposure. In summer and autumn, deciduous trees or shade sheds should be used to keep out the scorching sun, and the ground should be sprayed with water frequently. Rhododendron shoots in spring and autumn, mainly in spring. The optimum growth temperature is 15 ~ 20℃, and the growth stops when the temperature exceeds 30℃ or below 5℃. There is a short dormant period in winter, and then with the increase of temperature, the flower buds gradually expand. Generally, it blooms in the open field from March to May, and it blooms in high altitude areas as late as July and August. Greenhouse cultivation is in the north. 65438 can bloom from 0 to February. Rhododendron is resistant to pruning, and its hidden buds are easy to germinate after being stimulated, which can be used to control the tree shape and revitalize the tree. Pruning is usually carried out before May, and new branches can form buds in the same year. If it is too late, it will affect flowering. Generally speaking, new buds that germinate around early autumn can still be lignified. If the new buds form too late, they are vulnerable to freezing injury in winter. Evergreen or deciduous shrubs.

Seeding, cutting and grafting are commonly used for propagation, and layering and branching are also feasible. Sowing, evergreen azaleas are best sown with harvest, and deciduous azaleas can also store seeds until the next spring sowing. When the temperature 15 ~ 20℃, the seedlings will emerge in about 20 days. Cutting: Generally, semi-lignified branches of the current year are selected as cutting in May-June, and then shaded in shed. They can take root in 1 month at about 25 degrees Celsius. Rhododendron occidentalis takes root slowly, which takes about 60 ~ 70 days. Grafting, the propagation of Rhododendron occidentalis is widely used, often with twigs splitting, and the grafting time is not limited. The rootstock is mostly two-year-old Rhododendron, and the survival rate is over 90%. Wild rhododendrons and cultivated varieties from Mao Juan, Dong Juan and Xia Juan can be potted or planted in the shade. Xi Juan is potted all over the country, and the cultivated soil is mostly black mountain soil. Culture soil made of peat soil, Huangshan soil, humus soil, pine leaf soil, cinder and sawdust can be used as long as the pH value is between 5.5 and 7. O, good drainage, rich in humus. Pot filling is usually carried out in April or June 165438+ 10. Rhododendron roots expand slowly, so it is advisable to use 3-inch pots for 1 ~ 2 years, 4-inch pots for 3 ~ 4 years, change pots 1 time every 3 ~ 5 years, and trim roots at the same time. Water, according to the weather, plant size. Pot soil is dry and wet, which needs to be mastered flexibly. The water quality should be alkaline. When tap water is used, it is best to store 1 ~ 2 months in the water tank. Going out in mid-April is at the peak of growth, and the water demand is large; During the rainy season, water should be prevented; In the high temperature season from July to August, the evaporation is large, so it should be watered with the sun, and water should be sprayed on the ground and leaves at noon and night to cool down; 165438+1entered the room in early October. If there is heating in the room, the growth is still vigorous and the water demand is still large, especially when flowering and topping. If it is not heated indoors and grows slowly, it can be watered once every 3 to 5 days. Be thin, be fat and be diligent. For 2-4-year-old seedlings, in order to accelerate the formation of plants, the formation of new branches is often promoted by coring and bud picking. After the plant is formed, the diseased branches, weak branches and overlapping branches are mainly cut off, and thinning is the main method.