1、 The reason why the leaves turn yellow

1. Soil acidification: it likes a neutral soil environment. During the management period, the application of acidic chemical fertilizers such as stable manure, cake fertilizer and calcium superphosphate for a long time is easy to cause the soil to become sour, and the growth will slow down and the leaves will turn yellow slowly. At this time, an appropriate amount of organic fertilizer should be added to supplement trace elements

2. Temperature discomfort: the cold resistance and high temperature resistance of leek are not good. If the temperature in the greenhouse is above 35 ℃ for a long time, coupled with air drying, it is easy to lead to leaf burning and leaf drying. If cold air suddenly invades at this time, the whole plant will turn yellow. Be sure to pay attention to the temperature. When the temperature is high, ventilate more, spray water frequently to moisturize, and avoid the phenomenon of yellow leaves as much as possible

3. Infected with diseases and pests: during the management period, if the environment is not suitable, it is easy to be infected with diseases and pests, and yellow leaves will also appear at this time. Spray the medicine as soon as possible. It is recommended to use high-efficiency and low toxicity drugs. In addition, we should pay attention to prevention at ordinary times, so as to reduce diseases and pests

2、 Can the leaves turn red and eat

The red leaves of leeks are mostly caused by insects or diseases. It's best not to eat them again to avoid discomfort. In addition, be sure to clean before eating to avoid pesticide residues