When is the latest time to dig sweet potatoes?

The sweet potato was poached by the recent frost.

1. Generally, it should be dug in cold dew, and the sweet potato should be harvested in September-10 in most areas of northern China at the latest, which basically conforms to the growth law of sweet potato.

Sweet potato expands fastest in the temperature range of 20-25℃, and the expansion speed slows down after the temperature drops to 65438 08℃. When sowing wheat in double-cropping rice areas, the digging date of sweet potato is generally 10- 15 days earlier, while the sowing temperature of autumn wheat in northern areas is 16- 18.

2. The root tuber of sweet potato stops growing below 15℃, that is to say, sweet potato is harvested immediately after local wheat sowing, which is the stage with the highest yield of sweet potato, and it is unnecessary to continue planting sweet potato in the field.

3. The latest time to dig sweet potatoes is the local first frost, that is, when the instantaneous minimum temperature drops to 4℃ at night. Sweet potato will not germinate or freeze in the range of 10- 15℃, which is the best storage temperature of sweet potato. If the temperature is lower than 10℃, there is a danger of frostbite. If storage is needed, the local temperature should be reduced to above 10℃ to complete the harvest.

Sweet potato introduction:

Sweet potato is a high-temperature crop, which is an annual in the north and a perennial in the tropics. As long as the environmental conditions are suitable for the growth of sweet potato, the root tuber can always expand, so it has great potential to increase production and is the highest yield crop known at present.