1、 Remedies

Take the cactus out of the flowerpot and cut off the rotten place with sterilized scissors. If possible, it's best to disinfect it, and then put it in a ventilated place to dry. If it doesn't dry, it's difficult to survive. Insert it into the pot soil after the wound is dry. Don't insert it too deep to avoid decay. It's best not to water it before it grows again

2、 Preventive methods

1. Reduce watering

Reason: Cactus does not need too much water. If it is watered too much at ordinary times, it will produce ponding. In addition, in an airless environment, its roots are easy to rot and lead to the death of the whole plant

Solution: put it in a ventilated environment as far as possible. Water it after the soil is dry. Water it properly for daily maintenance. Don't water it too often

2. Proper fertilization

Reason: if the amount of fertilizer applied to cactus is not well controlled, it is easy to apply excessive fertilizer, or apply immature fertilizer, which may cause root rot

Solution: timely and appropriate amount of fertilizer should be applied. The amount of fertilizer should not be too much and the concentration of fertilizer should not be too high. It is OK to apply fertilizer once every 15 days during its growth period. It is best not to apply fertilizer in winter, or apply a small amount of fertilizer, so that the root will not rot

3. Adjust temperature

Reason: if the temperature is low in winter, the cactus will be frostbitten, resulting in root rot

Solution: the temperature should be properly adjusted. It is best to control the temperature above 5 ℃ in winter, and let it receive sufficient light during the day. The leaf surface can also be wrapped with a film to keep it warm