The bottom of the cactus is wrinkled and atrophied

1. Excessive watering

Reason: Cactus is a succulent plant and is particularly drought-resistant. If it is watered too much, causing waterlogging in the soil, it will easily lead to root rot, which will manifest as wrinkles and shrinkage at the bottom of the cactus. In severe cases, it will also cause the cactus ball to rot.

Solution: If the soil in the pot feels damp, dig out the cactus and check the root system. If there are rotten parts, remove them in time. Apply some carbendazim to the wound, let it dry, and then replant it in moist soil. The flowerpot for planting should not be too large, use a breathable clay pot.

2. The temperature is too low

Reason: Cactus likes warmth and is afraid of cold. In winter, it is best to ensure that the maintenance temperature is above 10℃. If it is below 10℃, reduce watering. If the temperature is below 0℃, the cactus will easily be frostbitten, which will manifest as yellow spots on the sphere and wrinkled and shrunken folds at the bottom of the plant.

Solution: Avoid applying nitrogen fertilizer in late autumn, and apply more phosphorus and potassium fertilizers to improve the cactus's resistance to frost; place the cactus in a heated room in winter, but keep it away from heating and geothermal heat; find a plastic bag to cover the cactus in winter, and open the bag for ventilation during the day.

3. Exposure to the scorching sun

Reason: Although the cactus is a succulent plant that likes the sun, it still needs to be properly shaded from the scorching sun in summer. Long-term exposure to the sun will cause the soil moisture to lose rapidly, causing the bottom of the cactus to wrinkle and shrink. Sudden exposure to the sun can easily sunburn the plant's ball.

Solution: The main thing to prevent is excessive sunlight in the summer. You can set up a shade net above the plant to block part of the light; or move the cactus to an east-facing balcony so that it can only be exposed to relatively soft light in the morning.