Every March-April in spring or August-September in autumn, the temperature is stable above 15 degrees, and the light and humidity are suitable, which is beneficial to the rapid germination of cowpea, but the specific planting time needs to be adjusted according to the local weather conditions.
Before sowing, the seeds must be carefully selected and then dried for 1~2 days. Usually, dry seeds can be directly sown, or they can be temporarily soaked in warm water of 25~30 degrees. Cowpea seeds can be taken out and dried after water absorption and swelling, and used to moisturize the skin before sowing.
When sowing, the method of sowing on demand is usually adopted, the hole spacing is 40×50 cm, and 2-3 seeds are put in each hole. Only 1-2 cm of soil is needed after sowing. After covering the soil, pour enough water and cover it with plastic film for heat preservation and moisture retention. However, we should be careful not to cover the film when sowing in summer, so as to avoid the failure of seed germination caused by high temperature under the film, which is not good for seed germination. Always use water to make the soil wet and germinate.
Prevention and control techniques of cowpea diseases and insect pests
1, mold
Cowpea is easy to be infected with mold, which will cause gray spots on plant leaves and wither and die in severe cases. When controlling cowpea mold, the branches and leaves of seriously infected plants should be cut off with sterilized sharp scissors to avoid serious situations.
2. Aphids
The main pest of cowpea is aphid, which eats the leaves of plants and causes their leaves to die. When controlling cowpea aphids, it is necessary to wipe off pests on plant leaves with paper towels dipped in alcohol to reduce the source of pests, and spray imidacloprid once a week to promote the healthy growth of cowpea.
3. Starscream
Starscream will crawl on the branches and leaves of cowpea and eat the leaves and fruits of plants. When controlling cowpea red spider, it is necessary to implement 3-4 years rotation to reduce germs and pests in the soil, and spray potassium permanganate on the soil surface for disinfection before planting to promote the vigorous growth of cowpea.