What should be noted in amaranth cultivation and production?

Amaranth, formerly named: amaranth, aliases: Joseph's coat, laoshaonian, laolaihao, three-colored amaranth, Latin name: Amaranthus tricolor, Amaranthaceae, Amaranthus annual herb, stems stout, green or red, often branched, hairy or hairless when young. Amaranth has soft and smooth leaves with a strong vegetable 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”, “xiecai”, “xingcai”, “xingcai”. In some places it is also called “hongmohu”, yunxiangcai, yuntiancai, hancai, etc.

Amaranth prefers warmth and is relatively heat-tolerant. The optimum growing 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 easily bolts and flowers. When cultivated in spring with suitable temperatures and longer daylight, bolting is delayed, the quality is tender, and the yield is high.

Geographical distribution of amaranth

Amaranth originated in China, India, and Southeast Asia, and has been eaten as a wild vegetable in China since ancient times. As a cultivated vegetable, it is mostly grown in China and India, and more in southern China than in the north. In various parts of southern China there are some amaranth varieties with excellent quality and high nutrition. Because amaranth has strong resistance, is easy to grow, is drought-tolerant, moisture-tolerant, and high-temperature-tolerant, and because pests and diseases rarely occur, amaranth has gradually become known and developed both in China and abroad. It is cultivated throughout the country and sometimes escapes to semi-wild status. It originated in India and is distributed in southern Asia, Central Asia, Japan, and other places.

Notes on amaranth cultivation and production

Amaranth is relatively sensitive to external conditions such as temperature, moisture, nutrients, and soil environment. Therefore, when the above requirements are met, amaranth grows well, has excellent quality, grows rapidly, has an extended commercial harvest period, and gives high yields. For this reason, special attention should be paid to the following aspects in production.

1. Sow at the right time and plant at a reasonable density

Under natural temperature conditions, the period suitable for amaranth growth, especially suitable for its commercial production, is not long. It is neither tolerant of low temperatures, nor does high temperature fail to significantly affect its quality and cause it to lose commercial value. As the saying goes, “June amaranth cannot pass the gate”, meaning that in most areas of Jiangnan in China, amaranth after the 7th lunar month cannot be sold. Amaranth is only suitable for growing under mild climatic conditions, and generally April to June each year is its suitable growing period.

Because the suitable growing period for amaranth is short, direct sowing is generally preferred for cultivation. Sowing can be done from “Yushui” to “Jingzhe”. Before sowing, fine-crumb and level the vegetable plot, apply 1500-2000 kg of water and fertilizer per mu as base fertilizer, sow 0.4-0.5 kg per mu, broadcast about 1000 kg of plant ash after sowing, and then cover with 0.5-1 cm of fine soil. After the seedlings emerge, spray clear water once every 2-3 days. After the seedlings grow 1-2 true leaves, topdress with 0.3% ammonium sulfate solution once every 5-7 days; after 4-5 true leaves appear, begin thinning and weeding; when they reach 13-15 cm in height, thin and finalize the seedlings at a spacing of 18-20 cm between plants and rows. Only by overcoming excessive density, improving the individual growth environment, and ensuring an appropriate number of seedlings per unit area can high-quality, high-yield commercial vegetables be cultivated.

2. Fertilize according to the weather and regulate moisture reasonably

In early spring the climate is changeable, and the early morning temperature is relatively low. Amaranth is especially sensitive to temperature and moisture, so watering and fertilizing should be done on sunny days at 9-10 a.m. or 4-5 p.m. After fertilizing, immediately spray the leaf surface with clear water to wash away fertilizer remaining on the leaves, so as to prevent the fertilizer concentration on the leaves from becoming too high under the sun and causing seedling burn. When the temperature rises in late spring and the minimum temperature reaches above 16°C, move watering and fertilizing earlier to early morning. During continuous rainy weather, do a good job of drainage and stop watering and fertilizing; instead apply old wall mud or broadcast granular fertilizer to prevent root rot from excessive water and lack of oxygen. Amaranth has a relatively large and strict nutrient demand, and attention should be paid to continuity in fertilizing, especially after each harvest, when fertilizer should be applied promptly and in sufficient quantity. Once it lacks fertilizer, growth will be poor. It is also very sensitive to whether moisture is appropriate. If moisture and nutrients are handled even slightly carelessly, leaf shrinkage, stunted plants, and difficulty in recovery may occur.

3. Adjust soil pH in a timely manner

Amaranth is suitable for growing in weakly acidic and neutral soils, and generally soil pH 6-7 is most suitable. However, soils in southern China are mostly acidic, with pH mostly between 4.5-5.5. In addition, farmers habitually apply human and livestock manure and urine, and the high uric acid content in human urine further intensifies soil acidification. Therefore, on the basis of applying plant ash or shell ash as base fertilizer, amaranth also needs frequent broadcasting of some plant ash as topdressing, so as to promote rapid growth and greatly improve the quality and grade of the commercial vegetable.