Cause: if the cold wind blows directly to the warm leaves, it will cause the leaves to lose green and form white spots.
Solution: when the wind is blowing, the wind should be carried away from the wind direction, and the tuyere should be gradually increased from small to large, and it should not be rushed. Or you can hang a plastic film on the inside of the wind, which can also prevent the cold wind from blowing directly.
Cause: if the temperature is higher than 0 ℃ for a long time, but lower than its normal growth temperature, then there are yellow and white chlorotic spots on the leaves, which may even lead to withering and death, and there will also be slow growth or the plant does not root.
Solution: find out the cause of low temperature, take heat preservation measures, control the temperature in the daytime between 25 ° C and 30 ° C, and at night not less than 10 ° C, preferably between 10 ° C and 18 ° C.