Key Technical Points for Open-Field Cultivation and Management of Amaranth in Summer

Amaranth, formerly known as: amaranth, also known as: Joseph's coat, old youngster, laolaisao, tricolor amaranth, Latin name: Amaranthus tricolor, Amaranthaceae, Amaranthus genus annual herb, stems stout, green or red, often branched, hairy or hairless when young. Amaranth has soft, smooth leaves and a rich flavor, sweet and fragrant on the palate, and has the effect of moistening the intestines and stomach and clearing heat. It is also called "fukui", "crab vegetable", "xingcai", "xingcai". In some places it is also known as "red mushroom tiger", yunxiangcai, yuntiancai, hancai, etc.

Growth habits of amaranth

Amaranth likes warmth and is fairly heat-tolerant. The optimum growth temperature is 23~27°C. Growth is slow below 20°C, and seed germination is difficult below 10°C. It requires moist soil but is not waterlogging-tolerant, and has no strict requirements for air humidity. It is a short-day vegetable, and under high temperature and short-day conditions it tends to bolt and flower. When cultivated in spring with suitable temperatures and longer daylight, bolting is delayed, the quality is tender, and the yield is high.

Open-field cultivation and management techniques for amaranth in summer

1. Selection of varieties

For open-field summer cultivation, it is advisable to choose large-leaf red amaranth, round-leaf amaranth, and pointed-leaf red amaranth, which have strong heat tolerance, strong drought tolerance, relatively strong resistance to pests and diseases, and high yield and good quality. ① Large-leaf red amaranth. The whole plant has 14 leaves; the leaves are relatively large, long ovate, with nearly entire margins, deep purplish red, and the leaf margins are green; the stem is light green, and the stems and leaf flesh of young plants are thick and tender, suitable for cooking and with a distinctive flavor. It can be harvested about 40 days after sowing. The general yield is 2500 kg per 667 sq m. ② Round-leaf amaranth. The whole plant has 15 leaves; the upper surface of the leaves is green, the underside is pinkish green, and the petioles and stems are green or deep purplish red; both stems and leaves have short white hairs. The stems and leaves of young plants are soft and suitable for cooking. Under warm conditions with sufficient water and fertilizer, it grows rapidly and can be harvested more than 20 days after sowing. The general yield is 2000 kg per 667 sq m. ③ Pointed-leaf red amaranth. The whole plant has 12 leaves; the leaves are relatively narrow and long, the petioles and stems are purplish red, and the leaves and stems are covered with short white hairs. The flesh of young plants is somewhat coarse and high in fiber, suitable for cooking. The general yield is 1500 kg per 667 sq m.

2. Making beds and sowing

Choose flat terrain, convenient drainage and irrigation, fertile and loose sandy loam or clay loam, and slightly alkaline soil. After harvesting the previous crop, prepare the land in time, applying 2000 kg of barnyard manure and 50 kg of diammonium phosphate per 667 sq m. After deep plowing and raking level, make flat beds 1.5 m wide. Direct sowing is generally used, with the seedlings harvested for consumption. Sow in stages from May to late June. Broadcast sowing is used, with 1 kg of seed per 667 sq m. After sowing, cover with soil 0.5 cm thick, press firm, and water to settle the soil.

3. Field management and care

Amaranth is a wild vegetable and is easy to manage; just keep the field moist regularly. Summer-sown amaranth emerges in 3 to 6 days. After emergence, weed in time and strengthen water and fertilizer management to keep the soil moist. During the hot midsummer period, it is also necessary to cover with shade netting to lower the temperature and preserve moisture, covering by day and uncovering at night, creating a suitable temperature environment for amaranth growth, which helps increase yield and improve quality. From sowing until the plants have 2 true leaves, choose a sunny day for the first topdressing; about 12 days later, carry out the second topdressing; after the first thinning harvest, carry out the third topdressing. After each topdressing, water in time; thereafter, topdress once after each thinning harvest. If the base fertilizer is sufficient, no topdressing is needed during the growing period.

4. Pest and disease control

Amaranth has relatively strong disease resistance. The main disease is white rust, and the pest is aphids. To control white rust, at the early stage of the disease, spray 50% metalaxyl-copper wettable powder at 700 times dilution, or 64% sandofan wettable powder at 500 times dilution, or 60% metalaxyl-aluminum-copper wettable powder at 600 times dilution. To control aphids, spray 40% dimethoate at 1200~2000 times dilution, or 2.5% kung fu emulsifiable concentrate at 4000 times dilution.

5. Timely harvesting

45~50 days after sowing, when the seedlings are 12~15 cm tall and have 5~6 leaves, carry out the first harvest, that is, thinning out some overly dense plants. After another 20 days, when the plants are 20~25 cm tall, leave 5 cm at the base and carry out the second harvest. After that, when the side branches have grown to about 15 cm, carry out the third harvest.