Different growth stages of flower stems in China need different temperatures. The optimum temperature for seed germination is 25 ~ 30℃, and the temperature for leaf growth is slightly lower, about 20 ~ 25℃. In this temperature range, the Chinese flower stems develop rapidly and can be harvested in 10 ~ 15d, but the Chinese flower stems are small and the quality is not good. The optimum time for the formation of flower stems in China is about 15 ~ 20℃ (daily temperature 15 ~ 20℃, night temperature 10 ~ 15℃). China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China However, when the temperature is above 20℃, it grows slowly, and it is difficult to grow above 30℃. The quality of Chinese flowering cabbage developed above 25℃ is poor. In winter, the flower stems are weak, which is easy to meet the needs of vernalization and low temperature. High temperature seriously affects pollen development and pollination, and the amount of seeds collected is reduced. Temperature affects bolting speed, and low temperature promotes germination, but the optimum temperature is 15 ~ 25℃.

lamplight

China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China and China. China, China, China, China, China, China, China, China, China and China. However, the whole growth and development process needs sufficient light, which affects photosynthesis, weak growth of Chinese flowering cabbage, low yield and poor quality.

3. Land

Flowering stems are not strict with soil. As long as the fertilizer and water are well solved, high yield can be obtained. Generally speaking, loam or sandy loam with strong water and fertilizer conservation ability and rich organic matter is better. At the same time, it should be noted that the flower stems grow faster. Loosen the soil after each watering to increase soil permeability and prevent soil hardening, which is beneficial to plant growth.

Step 4: Moisture

Flowering Roots China Flowering China Flowering China Flowering China Flowering China Flowering China Flowering China Flowering China Flowering China Flowering China Flowering China Flowering China Flowing China Flowing China Flowing China Flowing China Flowing China Flowing China Flowing China Flowing China Flowing China Flowing China Flowing China Flowing China Flowing China Flowing China Flowing. Water is closely related to the formation of flowering in China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China. However, if there is too much water and there is water in the field, the plants are more resistant to moisture, which is easy to cause root rot.

5. nutrients

The absorption of mineral nutrients by flower stems in China is the most, followed by potassium and the least. The ratio of absorbed nitrogen, phosphorus and potassium is 3.5: 1: 3.4. Every production of 1000kg Chinese flowering cabbage needs to absorb 2.2 ~ 3.6 kg of nitrogen, 0.6 ~ 1.0 kg of phosphorus and 0/.1~ 3.8 kg of potassium. Generally speaking, nitrogen fertilizer is mainly used for topdressing, but the demand for phosphorus and potassium fertilizer is obvious in the later stage, and phosphorus and potassium fertilizer can also be added as appropriate. China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China. However, the effect of nitrogen fertilizer and its yield-increasing effect are related to the variety and dosage of fertilizer. Xu Yuejin et al. (1997) studied the photosynthetic rate of three purple flower stem varieties (lines) under different nitrogen levels and densities. The results showed that the diurnal variation of photosynthetic rate showed a "lunch break" phenomenon, and chlorophyll content, leaf area index and specific leaf weight were positively correlated with photosynthetic rate. Increasing nitrogen fertilizer and reducing density were helpful to improve photosynthetic rate. Wu et al. (1993) studied the absorption and utilization of phosphorus by Viola yedoensis. Flowering China, China, China, China, China, China, China, China, China, China, China and China. However, during the growth period of Zizania latifolia, the absorption of phosphorus was the largest. The average phosphorus content of the whole plant is 0. 18% of the dry weight of the plant. In all parts of the plant, the phosphorus content of the main plant is more than 70% higher than that of the leaves and roots, and the phosphorus content of the secondary plant is more than 80% higher than that of the leaves and roots. Flowering in China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China, China. Yao Jianwu et al. (2002) found that nitrate accumulation in different genotypes of Chinese cabbage was very different. Among the varieties identified, the nitrate accumulation levels of Jiu Si Youqing, Chihua No.29 and Wancaixin No.2 were generally low.