Why should peanuts be planted after Grain Rain? Why should sweet potatoes be planted after Grain Rain?

There is a folk saying that goes "Don't plant peanuts before Grain Rain". In fact, in addition to peanuts, sweet potatoes are also best planted after Grain Rain. This is mainly related to the suitable temperature for the growth of the two crops. The temperature before Grain Rain is relatively low, and the temperature after Grain Rain is more suitable for the growth of peanuts and sweet potatoes.

Why should peanuts be planted after Grain Rain?

Grain Rain is the sixth solar term of the 24 solar terms and the last solar term of spring. The snow stops at Qingming and the frost stops at Guyu. This is a proverb that the ancients summarized about the weather of Grain Rain. After Grain Rain, it is the Beginning of Summer. The temperature rises faster. After Grain Rain, it is also the best time to sow and raise seedlings, plant beans, peanuts, sesame and other crops.

Because peanuts are a warm-loving crop. The best time to plant peanuts is when the temperature is above 15 degrees. When the temperature is below 13 degrees Celsius, the germination rate of peanuts will be affected, and seedlings will die or rot. Therefore, peanuts must not be planted when the temperature is too low. If the average temperature is difficult to maintain around 13 degrees around the Qingming Festival, the buried seeds will rot because they cannot germinate.

However, now there is the technology of mulching. It is not necessary to plant after the Grain Rain. The best planting time can be determined according to the climate and temperature of each place. Sowing in advance can improve the quality and yield of peanuts. Planting with mulch can also retain water and fertilizer, reduce peanut diseases and pests, and many other benefits.

Why can we plant sweet potatoes after Grain Rain?

Sweet potatoes are thermophilic crops and are not resistant to low temperatures. The suitable temperature for their growth is 18-32 degrees. When storing sweet potatoes, they must be stored in a cellar, and the cellar temperature must not be lower than 12 degrees.

Before planting sweet potatoes, seedlings need to be raised, and the seedling raising period generally takes 30-45 days. The growth temperature of sweet potato seedlings is above 15 degrees Celsius. When the soil temperature is below 9 degrees, the sweet potatoes will be frozen and rot. If it is below 15 degrees, the sweet potato seedlings will stop growing and may even be frozen to death when a cold wave comes.

During the seedling period, a greenhouse or plastic film must be used to ensure the appropriate temperature during the seedling period. If the temperature is too low, it will be detrimental to the growth of the seedlings and the sweet potatoes will rot. After the Grain Rain, the temperature gradually stabilizes and rises. Planting sweet potatoes at this time is conducive to normal growth.

What fertilizer is good for growing sweet potatoes?

Sweet potato is a potassium-loving crop. When applying fertilizer, it is necessary to increase potassium and reduce nitrogen. Especially in plains with fertile soil, it is important to reduce the application of nitrogen fertilizer when planting sweet potatoes to prevent the potato vines from growing vigorously and being difficult to control, resulting in only vines growing but no potatoes, small tubers and low yields. For overly fertile plots, you can even avoid applying nitrogen fertilizers and only use phosphorus and potassium fertilizers to achieve high yields.

Sweet potatoes are sulfur-loving crops, so potassium sulfate-type compound fertilizers should be selected when applying fertilizer, especially for sweet potatoes that are prepared to be stored in potato cellars. Applying potassium sulfate-type compound fertilizers will improve the quality of the sweet potatoes, reduce their moisture content, and allow for longer storage.