What are the main points of soilless cultivation management of rhododendron?

Soilless culture of western rhododendron: Because of its delicate habits, it is suitable for potted plants and more suitable for soilless culture.

1. Propagation of flower seedlings: basically similar to the propagation of seedlings in soil.

2. Selection of substrates: The substrates used to cultivate Xi Juan must meet the following conditions: (1) Provide acidic environment: pine needles, peat, sawdust, etc. Both are acidic substrates.

(2) The roots in the substrate are not dried up due to dry weather: for example, in Dandong and Jiangsu and Zhejiang regions, pine needles or sawdust are good cultivation substrates, and because of the high air humidity, the substrate has enough air permeability, which is beneficial to the growth of rhododendrons. It is best to choose the mixed substrate of peat and vermiculite or perlite in the dry areas of northern China such as Beijing.

(3) Water retention, fertilizer retention and air permeability: these are the same requirements for all cultivation substrates.

In view of the above situation, the relationship between acidity, ventilation and water and fertilizer conservation should be properly handled in the cultivation practice of rhododendron. For soilless culture, it can be considered that the acidity of the substrate should be appropriate, and good ventilation should be maintained to avoid leakage of the basin bottom. You can ensure nutrition and moisture by watering and filling nutrient solution.

3. Formula of nutrient solution: (1) pH: The concentration of hydrogen ions is 3. 16 ~ 3 1.63 micromole/L (pH 5.5 ~ 4.5), which means that the physiological acidity is strong and the most suitable environmental acidity of rhododendron roots is maintained.

(2) Total nutrition: provide all kinds of nutrients needed according to the growth needs of Rhododendron occidentalis. The proper proportion of nutrients must be met, otherwise it is easy to cause single salt poisoning.

(3) Large acid-base buffering capacity: the hydrogen ion concentration of the nutrient solution will not be significantly reduced due to the addition of alkaline substances. If the water quality is alkaline, the hydrogen ion concentration of the solution should not drop rapidly after adding water.

Xi Juan nutrient solution newly prepared by Beijing Institute of Landscape Science has good comprehensive performance. Specific formula: ① The ratio of nitrogen, phosphorus, potassium, calcium and magnesium in the early stage of plant growth is 17: 3: 5: 5: 2, and the trace elements of iron, manganese, zinc, copper and molybdenum are 7.6 mg/L of ferric sulfate heptahydrate, 2 mg/L of manganese sulfate, 0.5 mg/L of zinc sulfate and 0.65433 mg/L of copper sulfate pentahydrate respectively. (2) Potassium nitrate and potassium dihydrogen phosphate should be added to the formula during the flower bud differentiation in the late vegetative growth stage of plants. The ratio of major elements nitrogen, phosphorus, potassium, calcium and magnesium is18: 5: 8: 5: 2. Take 1 year-old seedlings as an example. During the vegetative growth period, 230 ~ 250 ml of nutrient solution was applied to each pot, once a week/kloc-0.

4. Scientific watering: Rhododendron is not alkali-tolerant. Usually, the concentration of hydrogen ions in groundwater used in cities is lower than 100 nm/L (pH is higher than 7). Watering azaleas with this kind of water will cause the leaves to turn yellow, fall off and even die. But you can set up a water tank where azaleas are planted, and put the water in the tank to dry for a few days. If some grass, tomatoes or orange peels are thrown in, the hydrogen ion concentration of water can rise above 100 nanomole/liter in about 7 days (the pH drops below 7). If you want to be clean, you can use vinegar essence or vinegar to adjust the hydrogen ion concentration of water. 500 ml water plus 1 tablespoon vinegar has a good effect.