How to grow cowpeas in summer? Detailed explanation of cultivation and management key points

Cowpea belongs to the legume family and is one of the oldest vegetable crops in the world. Mature cowpea seeds are kidney-shaped and come in various colors including black, white, red, purple and brown. The main production areas of cowpea in China are Shanxi, Shandong, Shaanxi and other places.

Varieties of cowpea for summer cultivation:

Qili Cowpea: The pods are emerald green, do not bulge with seeds at a high temperature of 38°C, and the pod color does not turn white. It has strong continuous pod-setting ability and high yield, with pods 65-75 cm long. Strong disease resistance. The disadvantage is that pods become shorter and curved under low temperature conditions. Suitable for sowing from April 20 to June 30 in the Yellow River basin, from mid-April to early July in the Yangtze River basin, from early April to early August in northern Guangxi, spring and summer sowing in Zhejiang and Fujian, and spring sowing in the Leizhou Peninsula.

Quanwang Cowpea: The pods are green-white in color, greener than Xiaowuye. Extremely high yield, strong adaptability, does not bulge with seeds at high temperature, does not curve at low temperature. Pods about 70 cm long. Suitable for spring sowing in North China and Northwest China, spring, summer and autumn sowing in the Yellow River basin, the Yangtze River basin and the Yunnan-Guizhou Plateau, early spring sowing in the Leizhou Peninsula, and winter sowing in Hainan.

Qili Zaosheng: The pods are green-white in color, thick-fleshed, extremely high yield, pods about 80 cm long, with particularly outstanding low-temperature tolerance; at a low temperature of 13°C the pods can still reach 70 cm long. The disadvantage is that it is susceptible to disease at the seedling stage. Suitable for planting in areas with relatively low rainfall.

Qimei: Highly disease-resistant, tolerant of poor soil, good pod shape, does not bulge with seeds, excellent pod tip finish, pods about 70 cm long, medium yield. Suitable for summer sowing in South China and Hainan, and planting in hilly areas of the Yangtze River basin.

Nutritional value of cowpea

Sweet and neutral in nature, it strengthens the stomach and tonifies the kidney. It contains protein that is easy to digest and absorb, as well as various vitamins and trace elements. The phospholipids it contains can promote insulin secretion, making it an ideal food for diabetic patients.

Nutritional analysis of cowpea:

Cowpea is rich in vitamin B, vitamin C and plant protein. It can calm the mind, regulate the digestive system, and relieve chest and diaphragm distension. It can prevent and treat acute gastroenteritis, vomiting and diarrhea. It has the effects of quenching thirst and strengthening the spleen, tonifying the kidney and stopping diarrhea, and replenishing qi and promoting body fluid production.

Cowpea provides high-quality protein that is easy to digest and absorb, an appropriate amount of carbohydrates and various vitamins, trace elements, etc., and can supplement the body's signature nutrients.

The B vitamins contained in cowpea can maintain the normal functions of digestive gland secretion and gastrointestinal peristalsis, inhibit cholinesterase activity, help digestion and increase appetite.

The vitamin C contained in cowpea can promote antibody synthesis and improve the body's antiviral effect.

The phospholipids in cowpea have the effect of promoting insulin secretion and participating in sugar metabolism, making it an ideal food for diabetic patients.

Nutrients in cowpea: vitamin A, vitamin B1, vitamin B2, vitamin C; minerals including iron, magnesium, manganese, phosphorus, potassium, etc.; protein and folic acid.

Key points of summer cultivation and management of cowpea

Summer cowpea refers to cowpea whose peak harvest period occurs under a high temperature of 35°C. Because of the high temperature, small temperature difference and large rainfall in this crop, the pods tend to bulge with seeds and pests and diseases are serious. Therefore, the cultivation techniques differ from spring. The cultivation goal is not to pursue high yield, but to have good market quality, strong disease resistance, and pod color suitable for the consumption habits of a specific market. The following aspects should generally be noted.

1. Variety selection

On the basis of ensuring suitable color, no seed bulging at high temperature and strong disease resistance, choose high-yielding varieties as much as possible.

2. Land preparation and fertilization

Apply 30 kg of three-element compound fertilizer per mu, 1 kg of borax (applied once every three years), 50 g of ammonium molybdate, and two cubic meters of organic fertilizer. When plowing, apply 400 ml of 40% chlorpyrifos to control underground pests. In the south, make high ridges; in the Yellow River basin, make high flat beds. Cover the ground with 60 cm black plastic film according to row spacing, which can both prevent weeds and preserve soil moisture and prevent waterlogging.

3. Sowing

Use 1.5-1.7 kg of seed per mu. The density should be thinner than spring planting, planting 2800-3000 hills per mu, two seeds per hill, with a row spacing of 1.5 m for two rows and a plant spacing of 30 cm. Be sure to cover with film first and then sow. It is best to germinate the seeds indoors before sowing.

4. Seedling stage management

The seedling stage of summer cultivation is very short, only 15-20 days from emergence to vine trailing. The main management points are disease prevention and fertilizer control. Generally, 40 ml of 10% myclobutanil emulsifiable concentrate is used as a root drench to control cowpea basal rot.

5. Vine-training stage management

From vine trailing to full trellis coverage, management focuses on controlling water and fertilizer, keeping the soil moisture in the yellow moisture state, that is, soil water content of 60-70%. Do not fertilize before the vines have covered half the trellis, and especially do not apply nitrogen fertilizer at all. Pay attention to controlling diseases and insect pests; generally use 60 ml of 10% myclobutanil mixed with chlorantraniliprole for spraying. When rainfall is heavy, add protective fungicides such as daming or metiram. When the growing point of the plant exceeds the trellis pole, pinch off the tip in time.

6. Pod-setting stage management

First, water and fertilizer management must keep up, especially nitrogen fertilizer must be applied sufficiently, but the amount applied at one time must not be too much, and the fertilization position must not be too close to the plant; too close and too much can easily cause leaf drop and rat-tail pods. Generally apply 10-15 kg of urea per mu, applied more than 40 cm away from the plants, and water in time after application.

Second, use pesticides reasonably and safely to control insect pests. The use of highly toxic pesticides is prohibited. Generally, spraying chlorantraniliprole once every 7 days can kill 95% of pests, with little residue.

Third, control diseases. In the early stage, the main ones are anthracnose and leaf spot; in the later stage, the main one is powdery mildew. Generally, therapeutic agents are mixed with protective agents, such as bromothalonil plus daming, myclobutanil plus metiram; triadimefon is prohibited. Ensure spraying once after each rain, or once a week.

Fourth, use foliar fertilizer reasonably, which can make the pods more attractive. Generally, when preventing diseases and controlling pests, spray a mixture of potassium nitrate and sodium nitrophenolate. Common foliar fertilizers include Gaoliaobao, etc.