What's the matter with the melon leaves turning yellow and not flourishing?

Yellow leaves are usually caused by two things:

The yellow leaves caused by the first situation are more complicated. Since the leaves are yellow, chlorophyll must be lacking. The lack of chlorophyll is often caused by the lack of elements such as magnesium, nitrogen, potassium, iron and zinc. It is difficult to know whether the lack of these elements is due to climate or soil or roots. The main reason for the lack of mineral elements is soil problems. In the case of continuous cropping in greenhouse, excessive use of chemical fertilizer causes secondary salinization of soil, which further inhibits the absorption and utilization of medium and trace elements by crop roots. The greater the application amount, the stronger the inhibition, forming a vicious circle. Therefore, in order to solve the yellowing problem of lower leaves of melon, soil salinization should be the focus, and spraying foliar fertilizer several times is difficult to achieve results.

The yellow leaves caused by the second situation should belong to bacterial leaf blight, and some people call it bacterial leaf spot. The wound is mainly caused by the friction of leaves, which is easy to spread in rainy and humid weather. Why are copper preparations or antibiotics not ideal? First, because the disease resistance of bacteria is enhanced, when the disease comes quickly, single medication often has little effect. Second, bad weather increases the difficulty of prevention and control, and the efficacy is often greatly reduced. It is suggested that streptomycin or neophytomycin or copper preparation can be sprayed in the early stage of bacterial blight, and a single drug will have a good effect. If the disease is at a high incidence, it is suggested to apply Shigao or other azole fungicides mixed with copper clothianidin or prochloraz, and add antibiotics appropriately.

Of course, rainy weather or tree crowns among plants can also cause leaves to turn yellow. In addition to improving the ventilation and light transmission conditions between plants, it is also quite beneficial to adopt the measures of spraying up and pouring down. Special reminder is that leaf yellowing often happens regularly, that is, when the vines are just hanging in early autumn, so it is necessary to take precautions in the early stage of element deficiency.