Detailed Guide to Cowpea Planting Methods and Cultivation Techniques
The cowpea is a warmth-loving food that is not tolerant of cold, so it is generally seen in summer. The cowpea has high edible value, and eating cowpeas regularly has the dietary benefits of supplementing nutrition and promoting digestion. This is also one reason people like it, and therefore many people want to grow it.
Cowpea Cultivation Techniques
1. Selection of good seed: Cowpea can be cultivated in spring, summer and autumn in the Wuxi area, and its growing season is long. Appropriate varieties must be selected according to the climatic conditions of each season. The varieties I commonly use are the Zhi cowpea series, the Yang cowpea series, the Nanjing Xingguang series, Yandai cowpea, Qicun cowpea, Bacun cowpea, ground cowpea, etc.
2. Cultivation season and sowing period: For early spring cowpea, sowing and raising seedlings can be done in greenhouses and other facilities from late March to early April; after mid-April, direct sowing with plastic film mulch can be done; after late April to early May, direct sowing in the open field can be done. The sowing period for spring and summer cowpea can generally continue to early to mid-July. Autumn cowpea is sown from July to early August, mainly Qicun cowpea and Bacun cowpea.
3. Land preparation, bed making and basal fertilizer application: Cowpea should not be continuously cropped and requires rotation for more than two years, otherwise diseases are likely to occur. After the previous crop is harvested, plow deeply 2O-3O cm, apply 3OOO kg of basal fertilizer per mu, 25-3O kg of superphosphate, 5O-75 kg of plant ash or rice husk ash, or 1O-2O kg of potassium sulfate. For acidic soil, an additional 75-1OO kg of lime may be applied as appropriate, then break up the soil and rake it level to make high beds 1.3 m wide including the ditch.
4. Reasonable close planting: Because early spring cowpea faces low temperatures and abundant rain, seedling raising and transplanting are advocated. After the seedlings emerge, they should be planted when the first pair of true leaves has not yet unfolded. Transplanting should follow the principle of planting small seedlings and planting early. When planting, plant two plants per hole. Summer and autumn cowpea mostly use direct sowing, with 3-4 seeds per hole at the least and 4-5 seeds at the most, and after emergence, thin to leave two plants per hole. The sowing density is 0.8-1 m between rows and 0.26-0.33 m between plants.
Cowpea Planting Methods
Although cowpea has a well-developed root system, its roots have weak regeneration capacity, so it is suitable for transplanting small seedlings. Generally, plant when the cotyledons have unfolded and the first pair of true leaves has not yet fully unfolded; those raising seedlings in nutrient pots may delay transplanting appropriately. Transplanting should preferably be done on a clear day at the end of a cold spell and the beginning of warmer weather. Before transplanting, water the seedling bed thoroughly, then lift the seedlings, discarding abnormal seedlings such as those with missing cotyledons or distorted true leaves. Cowpea is transplanted in double rows, with a hole spacing of 24-27 cm and 2-3 plants per hole. When transplanting, the opening in the plastic film should be small, and after transplanting, water at the roots immediately, then seal the opening with soil.
Fertilizer and Water Techniques for Cowpea
1. Before cowpea flowers and forms pods, it has low requirements for water and fertilizer, and management should focus on control. If the basal fertilizer is sufficient, generally no additional fertilizer is needed, and in dry weather, appropriate watering may be done. If there is too much water and fertilizer, the stems and leaves grow excessively, causing the flower cluster nodes to rise and their number to decrease, and it is easy to form empty vines in the middle and lower parts. When the first flower cluster sets pods and the flower clusters on the following few nodes appear, combine topdressing with one watering, applying 10-15 kg of compound fertilizer per mu and irrigating 20-30 cubic meters.
2. After pod setting, keep the soil moist frequently, and irrigate and topdress again every 1-2 weeks to maintain vigorous plant growth and flowering and pod setting. When entering the peak pod harvest period, more water and fertilizer are needed, and another irrigation and topdressing may be done, applying 10 kg of urea per mu, 20-25 kg of superphosphate, 5 kg of potassium sulfate or 40 kg of plant ash, and irrigating 20-30 cubic meters per mu. If the supply of water and fertilizer is insufficient, the plants are prone to decline in growth, with flower and pod drop.
Pest Control for Cowpea
1. Like common bean, cowpea should use integrated control measures against diseases and pests. The main measures are selecting disease-resistant varieties to enhance disease resistance, practicing crop rotation with a change of crop once every 2-3 years, cleaning the field, and increasing basal fertilizer and phosphorus and potassium fertilizers, etc. For the control of cowpea mosaic virus disease, the aphid vector that transmits the disease should be controlled promptly. For other diseases, chemical control should begin at the early stage of onset, once every 7-10 days, spraying 2-3 times in succession. The pesticides used are the same as for common bean.
2. For the control of the legume pod borer, spraying should begin at the bud stage, once every 7-10 days. This can control the damage. Also note that when spraying during the harvest period, it should be done after harvest to avoid contaminating the product.
When planting cowpea, site selection should be done well; cowpea is not tolerant of waterlogging, so drainage should be done well. Then choose the right time for transplanting. Field management after planting is also very important: fertilize and water at the right times, and also do a good job of pest control, so as to ensure the later growth of cowpea.