The Latest Cowpea Planting Techniques and Methods Tutorial

Cowpea, also known as long bean, long podded cowpea, yardlong bean, asparagus bean, rice bean, kidney bean, banded bean, kelp bean, and chopstick bean, is an annual herbaceous plant of the genus Vigna in the Fabaceae family. Cowpea is eaten for its tender pods. It is fairly rich in nutrients and can be stir-fried, served cold with dressing, salted, processed into pickles, or dried into cowpea strips. Because cowpea has good heat tolerance, it is a heat-resistant variety that fills the summer gap. Below, the editor will introduce cowpea planting techniques for everyone.

Growth and Development Characteristics of Cowpea

In the individual development of cowpea, taking the vining type as an example, from sowing to pod maturity or seed maturity, it can be divided into four stages: the seed germination stage, the seedling stage, the vine-running stage, and the flowering and podding stage.

1. Seed germination stage. The process from seed sprouting to the unfolding of the first pair of true leaves is the seed germination stage. The cotyledons emerge from the soil and do not carry out photosynthesis; they rely on stored nutrients that are broken down and used during germination. Once the first pair of true leaves unfolds, photosynthesis can begin and the plant can live independently.

2. Seedling stage. From the unfolding of the first pair of true leaves to having 7-8 compound leaves is the seedling stage. During the seedling stage, the internodes are short, the stem is upright, and the root system gradually spreads. Afterward, the internodes elongate, the plant can no longer stand upright and grows by twining, and at the same time the axillary buds at the base begin to become active, so it enters the vine-running stage.

3. Vine-running stage. From having 7-8 compound leaves to the plant showing flower buds is the vine-running stage. During this period, the main vine elongates rapidly, the base usually begins to send out lateral vines from the axillary buds of the first pair of true leaves and the 2nd-3rd nodes, and root nodules also begin to form.

4. Flowering and podding stage. From the plant showing flower buds to the end of pod harvesting or seed maturity, this generally lasts 50-60 days. For a single flower, from the start of differentiation to the formation of the floral organs takes about 25 days, from flower bud appearance to flowering takes about 5-7 days, from flowering to the commercial maturity of the pod takes about 9-13 days, and to the physiological maturity of the pod requires another 4-10 days, varying with variety and cultivation season.

Growing Environment for Cowpea

1. Temperature. Cowpea tolerates high temperatures and does not tolerate frost. The suitable temperature for germination is 25-35°C, and the suitable temperature for growth and development is 20-25°C. Above 35°C or below 15°C, growth and podding are affected. When the temperature approaches 0°C, the plants will suffer cold damage.

2. Light. Cowpea is not sensitive to day length, and only a few varieties have strict requirements for day length, being suitable for growth in short-day seasons. Generally speaking, short days can accelerate growth and development and promote earlier maturity. Cowpea likes sunlight. During the flowering and podding period, if light is insufficient, it will cause flower and pod drop.

3. Water. Cowpea is a vegetable with moderate water consumption and has relatively strong drought resistance. Too much soil moisture can easily lead to reduced germination rate, root rot and dead seedlings, and flower and pod drop, and is also unfavorable to the activity of rhizobia. Insufficient soil moisture will inhibit growth and development and affect yield.

4. Soil. For planting cowpea, well-drained, loose and fertile soil is most ideal. The most suitable soil pH is 6.2-7. Cowpea requires complete fertilizer with nitrogen, phosphorus, and potassium. Since the rhizobia of cowpea are far inferior to those of other leguminous plants, nitrogen fertilizer should be appropriately increased. At the same time, applying an appropriate amount of phosphorus fertilizer can promote rhizobial activity and increase yield.

Cowpea Planting Techniques

1. Selection of good varieties: Cowpea can be cultivated in spring, summer, and autumn in the Wuxi area, and the growing season is long. Appropriate varieties must be selected according to the climatic conditions of each season. Generally, the varieties I commonly use are the Zhijiang series, Yangjiang series, Nanjing Xingguang series, Yandai cowpea, Qicun cowpea, Bacun cowpea, ground cowpea, and so on.

2. Cultivation season and sowing period: For early spring cowpea, sowing and seedling raising can be carried out in greenhouses and other facilities from late March to early April. After mid-April, direct sowing with plastic film mulch can be done, and 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 avoids continuous cropping and requires crop rotation for more than two years, otherwise diseases are likely to occur. After the previous crop is harvested, deep plow 20-30 cm, apply 3000 kg of basal fertilizer per mu, 25-30 kg of superphosphate, 50-75 kg of plant ash or rice husk ash, or 10-20 kg of potassium sulfate. For acidic soil, an appropriate additional application of 75-100 kg of lime can be made, then break up the soil and rake it level, and make high beds with a width including ditches of 1.3 m.

4. Reasonable close planting: For early spring cowpea, because of 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. When planting, the principle of planting small seedlings and planting early should be followed. 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. 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.