What does it mean to plant melons and beans before and after Grain Rain?

The meaning of this proverb is as follows:

When the solar term arrives in Grain Rain, the rain moistens the earth, which is the best time to sow seedlings and order beans. According to the model website, Grain Rain is the sixth of the 24 solar terms. April 20th or 2 1 literally means sowing rain, so it is called Grain Rain. On this day, there is always plenty of rain and the temperature rises. It is a good time to sow seedlings and plant melons and beans, which is of great benefit to the growth of cereal crops. According to experience, the ancients came to the proverb that Grain Rain planted melons and beans before and after.

The solar term in Grain Rain is generally in April, and peanuts, sorghum, millet, sesame, soybeans, kidney beans, beans, wax gourd, watermelon, pumpkin, melon, loofah, zucchini, eggplant, pepper, tomato, spring corn, rape, lettuce, oil wheat and so on can be planted. There may be little rain in the north, but more rain in the south. So before and after Grain Rain, the temperature was high and the rain was frequent. Therefore, according to the weather changes, we should appropriately increase or decrease clothes and pay attention to health care.