A Detailed Guide to Kidney Bean Cultivation Techniques, Easy for Beginners Too

SummarySeed selection: choose seeds that are large and plump, free of pests, diseases and damage. Land preparation: plow in advance to improve soil fertility and apply sufficient base fertilizer. Sowing: sow from late April to early May, with a sowing depth of 10-15cm. Close planting: follow the principle of sparse sowing in fertile land and dense planting in lean land, with a seeding rate per mu of generally 8-10kg. Management: thin and finalize seedlings, timely weed, earth up, level the ridges, insert poles, build trellises and pinch off the growing tips, and actively prevent pests and diseases. Harvesting: pick each batch as it matures.

The scientific name of the kidney bean is Phaseolus vulgaris (commonly known as the second-season bean or four-season bean), of the genus Phaseolus in the Fabaceae family. The kidney bean originated in Mexico and Argentina in the Americas, and was only introduced and cultivated in China at the end of the 16th century. Kidney beans are rich in nutrients and high in protein content; they are both a vegetable and a grain, and are an important agricultural by-product for earning foreign exchange through export.

1. Selecting good varieties

Good varieties are the key to increasing the yield, quality and commercial value of kidney beans. In areas above 2000 m in altitude, large white kidney beans and large speckled kidney beans are mainly used. Before sowing, seed grading should be carried out, selecting seeds that are large, plump, highly uniform, consistent in luster, and free of pests, diseases and damage. Before sowing, sun the seeds for one to two days to promote uniform germination and prevent seed rot when sowing at low temperatures in early spring.

2. Fine land preparation

Fields for planting kidney beans must be plowed in advance, and the soil clods sunned to help improve soil fertility. First choose soil that is deep, of medium fertility, with a low groundwater table, good drainage, ventilation and sunshine, and relatively high organic matter content, whether acidic or slightly acidic. Apply sufficient base fertilizer: before land preparation, broadcast 1500-2000 kg of farmyard manure per mu; before sowing, use 25 kg of compound fertilizer per mu as seed fertilizer, but be sure to avoid phosphorus and potassium coming into contact with the seeds. The planting field should be kept deeply plowed with broken clods, and trenching, digging holes and sowing should be done the same day to reduce water evaporation and loss.

3. Timely sowing

Large white kidney beans are not suitable for continuous cropping; plant them in alternation with corn or potatoes every other year. The best sowing period for kidney beans is April 20 to May 5, that is, from Grain Rain to the Start of Summer. Take advantage of moisture-retaining soil for planting, with deep holes and deep sowing, so as to maintain soil moisture and ensure a full stand at one time; the sowing depth is 10-15cm, with about 6cm of soil covering.

4. Rational close planting

Kidney beans are cultivated on ridges; they like moisture but fear waterlogging, and ridge cultivation can raise soil temperature, help drainage and moisture removal, and maintain soil permeability. For pure kidney bean planting, form ridges with a row spacing of 2.0-2.5 chi, with 2000-2500 holes per mu, using 5-6 kg of seed per mu, sowing 3-4 seeds per hole. For top-grade fields, 1500 holes per mu, with a planting specification of 90 cm × 50 cm; for medium and lower-grade fields, 1600-1800 holes per mu, with a planting specification of 90 cm × 40 cm. The seeding rate per mu is generally 8-10 kg, and pure planting is generally done by digging holes and sowing in single rows. Rational close planting should follow the principle of sparse sowing in fertile land and dense planting in lean land. Fertile land uses its soil fertility and relies on the superiority of individual plants to achieve high yield, while lean land uses the superiority of the population to increase yield.

5. Field management

1. Finalizing and thinning seedlings: do this when the seedlings have 2-3 true leaves; according to the requirements, keep enough strong seedlings and remove weak and deformed seedlings. Keep 2-3 seedlings per hole.

2. Management before vine running: timely weed, earth up, level the ridges and insert poles, which helps ventilation and light penetration, makes pods plump and improves product quality.

3. Build trellises in time and adjust the plants: when the seedlings are 30 cm tall, insert supports and guide the vines onto the poles; insert one bamboo or wooden support per hole, with a length of about 2 m or more, to prevent wind damage. If they are not firmly inserted the first time, insert them again after a soaking rain.

4. Topping and pinching: kidney beans have many side branches, and their stems and leaves are luxuriant and crowd each other, affecting ventilation and light penetration, which often leads to flower and fruit drop, so excessive side branches should be properly removed. Kidney beans produce many flowers but set few pods; in order to concentrate nutrients to supply the lower flowers, remove part of the flower stalk tips early, so that the seeds become plump. Most pods set by large white kidney beans after August cannot mature, so at this time the growing tips of the main and side vines should be removed, causing the plant to form a short bushy shape, reducing height, increasing the number of flowers and pods, concentrating nutrients in the pods and promoting early maturity.

5. Disease control: mainly powdery mildew, anthracnose and mosaic virus, controlled with Bordeaux mixture, lime-sulfur mixture and the like.

6. Pest control: mainly cutworms, flea beetles, leaf rollers and bean pod borers. Cutworms can be manually captured and killed during farming operations such as plowing and sowing; other pests can be controlled with plant-source pesticides such as pyrethrum.

6. Timely harvesting

Pick each batch as it matures. The pod maturation period of kidney beans lasts more than a month, and early and late pods are not consistent; in addition, since it is the rainy season, if mature pods are not harvested in time they are prone to mildew and spoilage, or the seed coat turns black, affecting the commercial price. Therefore harvest in batches, place them with the pods in a cool place to air-dry, do not expose them to strong sun, and thresh them all at once before selling. In this way the seeds have good color and high plumpness, which can effectively raise their commercial grade.

7. Seed selection and retention

As the saying goes, “select seeds year after year, and the yield rises step by step.” The yield of individual kidney bean plants varies greatly, so in the field select early-maturing, high-yielding individual plants, tag them and harvest and store them separately. Selection criteria: first, many pods, especially many and concentrated pods on the lower part; second, more and plump seeds per pod on average. On the basis of plant selection, carry out seed grading as well, for even better quality.