Cultivation and pest control techniques of rhododendron

Rhododendron, also known as rhododendron, sheep horn flower, rhododendron, rhododendron, rhododend There are single, semidouble, double, etc., the flesh is mostly red, there are bright red, pink, pink, red, purple, yellow and other colors. there are pure white, golden yellow, staring yellow, green lotus and other colors, or mixed with Banzhen, stripes and so on. There are more than 800 species of plants of the same genus, most of which are produced in China. They are traditional famous flowers in China, one of the "top ten famous flowers" in China, and valuable dragon trees for urban greening and garden courtyard decoration, which can be potted or used as pile scenery. The wood of quail flower is hard and can be used for carving, and the roots, leaves and flowers can be used for medicine.

1. Reproduction. The propagation of rhododendron can be carried out with picking and sowing when the seeds are mature; cutting propagation can also be carried out before germination in February, from early June to early July and from late August to early September; strip propagation is carried out in the Meiyu season; split propagation is carried out in combination with transplanting; grafting was carried out in February and Meiyu season in spring and August-September in autumn, and the sturdy rhododendron was selected as rootstock, and the grafting methods such as split grafting, web grafting and relying on grafting were used.

2. Transplant. Azaleas like cool, moist and semi-shady environment, avoid hot sun exposure, like acid soil, more hardy, can be cultivated in the south of Huaihe River in China. When planting, choose a suitable place, dig planting holes or ditches that are more than 50 centimeters wide and 50 centimeters deep, and apply an appropriate amount of high-quality mature farm manure or municipal garbage as base fertilizer. Transplanting is often carried out in early spring or plum rain season, it is best to bring earth ball transplant. The seedlings are raised in a nutrition bowl and can be transplanted at any time. Within 1 month after planting, it should be watered twice a day and sprayed with foliar water (fog) several times a day. After sprouting in spring to early autumn, organic liquid fertilizer and phosphorus and potassium fertilizer were applied twice a month, and foliar fertilizer was sprayed at the right time. Timely watering in dry season, pay attention to drainage in rainy season, avoid stagnant water. High temperature in summer and early autumn should be properly shaded, and foliar water (fog) should be sprayed once a day in the morning and evening. Trim properly once a year after flowering.

3. Potted plants. Rhododendron in addition to ground planting green ornamental, can also be potted trees or tree stumps bonsai, known as the stump bonsai tree species "Rocks of Eighteen Scholars" one of the laudatory name. In addition to artificial reproduction and cultivation, bonsai can also be selected to dig wild tree stumps in the mountains between February and March. The spring or plum rain season uses the "cut-and-tie method" modeling. The basin soil is required to have a PH value of 4.5 min 6.5, which is loose and permeable and rich in humus. It can be mixed with 5 parts of loose mountain mud, 2 parts of rotten leaf soil or peat, 2 parts of mature high-quality farm manure or municipal garbage, and 1 part of fine river sand. The basin is selected according to the shape. Transplanting should be carried out between February and March in spring or September in autumn. After getting into the basin, it should be placed in a place where there is no direct sunlight and sufficient scattered light, and it is appropriate to often water and spray foliar water to keep the basin soil and environment moist. When the new branches grow vigorously, they should be moved to the half-yin and half-yang place for maintenance, and the basin should be fertilized and trimmed after a year of survival.

4. Maintenance. Rhododendron bonsai should be kept in a bright and moist place at ordinary times, and should be watered frequently to keep the soil moist and avoid stagnant water in the basin. In summer and early autumn, sunshade nets and bamboo curtains should be used to cover 50-60% of the sun, avoid strong direct sunlight, and water and spray foliar water once every morning and evening. Watering should be reduced appropriately after early autumn and winter to keep the basin soil moist and slightly dry. In the south can be in the outdoor leeward, sunny place to winter, in the north should be moved into the indoor winter, to maintain a room temperature of about 10 degrees. In growing season, thin organic fertilizer and phosphorus and potassium fertilizer should be applied every 10 days, liquid fertilizer should not be applied in plum rain season, biscuit fertilizer or compound flower fertilizer should be applied in pot, and fertilizer should be stopped in flowering, high temperature season and winter dormancy period. During the growth period, proper coring and sprouting should be carried out at the right time. When the buds grow to a certain size, the buds should be moderately thinned, and the branches should be pruned properly after anthesis and during the dormant period in winter. Turn the basin and change the soil every 2-3 years (medium-sized and large bonsai can be more than 4 years) after flowering, and replace about 1-2 old soil, which can be combined with appropriate root-lifting treatment to make its roots and claws exposed, so as to improve the ornamental effect.

5. Main pest control

Red spider. It can be sprayed with 40% dimethoate 1500 Mel 2000 times, 58% wind thunder excited EC 1500 Mel 2500 times, and so on.

Military worm (pear net bug). Can be sprayed with 1000 times of 50% fenitrothion.

Tea moth (bag worm, bag moth). It can be sprayed with 2000 times of trichlorfon.

Tea leaf roll moth (armyworm). The adults can be trapped and killed by black light, and the larvae can be sprayed with 8000 times of 20% diflubenzuron suspension and 2000 times of 20% diflubenzuron.

Inchworm. Black light can be used to trap and kill adults, and 20% chrysanthemum EC is used to kill larvae, such as 2000 times EC and 25% sharp mango EC 800Mel 1000 times.

6. Prevention and control of major diseases

Brown spot. It can be sprayed with 1000 times of thiophanate methyl and 800 times of Dysen zinc. Spray every 5 times every 7 days. Spray 3 Mel 5 times according to the condition.

Root rot. Pay attention to strengthen the cultivation management, keep the soil moist and loose, avoid stagnant water, irrigate the roots with 12% green copper EC 800Mel 1000x solution or Luheng No.1 3000 times solution at the initial stage of the disease, irrigate the roots once a week for 2 times continuously. When the disease is serious, the plants should be dug up from the soil in time (pots or bonsai should be turned in time to change the soil), wash off the root soil, cut off the diseased roots, and then use 12% oleic acid copper EC 600x solution. Soak the roots of Luheng No. 2 for 30 minutes, then rinse the roots with clean water, then use 75% chlorothalonil wettable powder 1000 times, or 50% carbendazim wettable powder 1000 times, add appropriate amount of fine red (yellow) soil, stir into thick mud, dip in the roots to be planted, and re-dig holes to loosen the soil (pots and bonsai should be replaced with loose new culture soil) The fungicides such as 1000 times solution of 12% turpentine copper EC or 1000 times solution of 50% turpentine copper EC, 600 times solution of Luheng 2 and 600 times solution of manganese germicidal wettable powder were sprayed once a week after planting. It is best to use two or more kinds alternately and spray 3 Mel 5 times in a row.

Leaf swelling disease (cake disease). Strengthen cultivation management, pay attention to environmental ventilation, light transmission, diseased leaves and tips should be removed thoroughly and destroyed in time. Before spring germination, plants are sprayed with 1 Bomedo stone sulfur mixture. During the development of new leaves, O.5 Bordeaux stone sulfur mixture or 1% Bordeaux solution is sprayed on the leaf surface for 3 times, once every 710 days.