What can be planted in Langfang in early April?

Cucumber, fennel, eggplant. In the natural environment, the soil temperature in Langfang can rise to 10 degrees four or five days before Tomb-Sweeping Day gas. Therefore, the earliest time to sow corn in Langfang is four or five days before Tomb-Sweeping Day gas, that is, from the end of March to the beginning of April. In the past, farmers planted corn here with two agricultural proverbs, namely, "Before Qingming, they planted it by wind, and after Qingming, they planted it by water". That is to say, before Qingming, the soil moisture evaporates slowly and the soil is moist, so the wind can take root. After the Qingming Festival, the soil moisture evaporates quickly, and the soil is prone to drought, so it must be moistened by rain to take root. No matter how it takes root, this agricultural proverb also shows that in the past, corn was planted in an open field as early as the end of March before Tomb-Sweeping Day.