1、 Improper watering

Reason: watercress Green likes a humid environment during its growth, but if it is not watered properly and too much, it will cause a large amount of ponding in the soil, because the roots are difficult to breathe, resulting in the gradual decay of the roots. The water temperature is also a very important reason. If the water used for watering is too cold, it will also lead to blackening and black spots on the plant leaves

Solution: control the amount of water when watering. If there is water, put it in a well ventilated place to promote the evaporation of excess water as much as possible

2、 Improper fertilization

Reason: reasonable fertilization can promote the growth of watercress green. Once too much fertilization or application of non rotten organic fertilizer, it may burn the root and make it difficult for the plant to grow normally

Solution: rotten fertilizer must be selected for daily fertilization. If the fertilization is too strong, it should be watered and diluted appropriately

3、 The temperature is too high

Reason: Douban Green doesn't like hot weather. The high temperature period in summer is unfavorable to growth. At the beginning, it will lead to black spots. If the situation is serious in the later stage, it will directly cause decay

Solution: measures should be taken to prevent strong light in summer. When the temperature is high, move to a ventilated and cool place to raise it

4、 Lower temperature

Reason: not only the high temperature will cause black spots, but also the low temperature in winter will cause black spots

Solution: in winter, you must move to a warm room. You can't be frozen outdoors. Keep the temperature above 10 ℃