Detailed Explanation of the Causes and Control Methods of Yellow Leaves in Leafy Vegetables

In our daily lives there are quite a lot of leafy vegetable varieties, but during their cultivation the phenomenon of yellowing leaves is often encountered, which seriously affects farmers' economic returns. So what causes yellow leaves in leafy vegetables? And how should they be controlled? Let's take a look together.

I. Yellow leaves in leafy vegetables

1. Water-induced yellowing. This kind of yellow leaf is actually caused by overwatering or watering too frequently during cultivation. The characteristic of water-induced yellowing is that the old leaves show no obvious change, but the young leaves turn yellow.

2. Fertilizer-induced yellowing. Fertilizer-induced yellowing, as the name suggests, is caused by fertilizing too frequently or at too high a concentration. Its characteristic is that the young leaves are rather thick and fleshy, glossy, and uneven.

3. Drought-induced yellowing. Drought-induced yellowing is caused by a lack of water. Its characteristic is that the old leaves turn yellow first, from top to bottom. If watering is not done in time, it can also cause the whole plant to turn yellow and wither, and even the death of the plant.

4. Starvation-induced yellowing. Completely opposite to fertilizer-induced yellowing, it is caused by applying too little fertilizer. If the fertilizer concentration is too low and the interval between fertilizations is too long, this situation can also occur. Its characteristic is that the young leaves and tender stems turn yellow first. If fertilizer is not applied in time, it can also cause the death of the whole plant.

II. Control techniques

1. Thinning flowers and fruits

After the temperature rises again, the growth rate of vegetables speeds up. At this time the nutrients absorbed by the root system are limited and cannot meet the needs of plant growth and development, so yellow leaves appear. At this point the plant's consumption of nutrients should be reduced in time, and the most effective method is to thin flowers and fruits and promptly remove the lower old leaves, so as to meet the vegetables' nutritional needs.

2. Spraying foliar fertilizer

In addition, when root absorption cannot meet the plant's consumption, the method of fertilizing outside the roots can be adopted to supplement nutrients, and foliar fertilizer is effective for this. Try to apply foliar fertilizers containing humic acid, amino acids, and boron, magnesium, zinc, etc., which can regulate crop growth, promote the leaves to recover as soon as possible, and enhance plant vigor.

3. Choosing suitable root-nourishing fertilizers

Many fertilizers on the market can promote plant rooting. Although they regulate crop growth, promote the leaves to recover as soon as possible, and enhance plant vigor quickly, the survival rate is low and the plants are very likely to die under adverse environments. In addition, root growth and development will also compete for nutrients, which instead aggravates the yellow leaf phenomenon. Therefore, when choosing rooting-type products, choose ones that can both promote roots and rooting, improve the root system's own resistance to adverse environments, and also ensure sufficient nutrients such as nitrogen, phosphorus and potassium.

4. Temperature control

In spring the outside temperature rises quickly, so attention should be paid to regulating the temperature inside the greenhouse to avoid too rapid a temperature rise and to avoid acute wilting. Generally the temperature should not exceed 28-30 degrees; when the temperature is too high, ventilate and cool down in time.

The above is an introduction to the causes and control methods of yellow leaves in leafy vegetables. We hope it can help you. To learn more related knowledge, please stay tuned to us.