Cultivation techniques of watercress

Watercress, which originated in Europe, is a perennial aquatic herb in the genus Cruciferae, also known as watercress, watercress, watercress and so on. It is cultivated in Heilongjiang, Hebei, Shanxi, Shandong, Henan, Anhui, Jiangsu, Guangdong, Guangxi, Shaanxi, Sichuan, Guizhou, Yunnan, Xizang and other regions. Let's take a look at watercress cultivation techniques.

Growth habits of watercress

Watercress likes cold, cool and humid environment, the suitable temperature for growth is 15: 25 ℃, the optimum temperature is about 20 ℃, and the growth is slow below 10 ℃. It can endure many frosts for a short time. If the temperature is about 0 ℃, it can survive the winter safely in the open field. If the temperature is higher than 30 ℃, the leaves are prone to yellowing or wilting. Good light is required in the growing period, and when the light is insufficient, the growth of stems and leaves is weak and the yield is low. The suitable pH value of neutral loam with strong water conservation and fertility conservation is 6.5-7.5.

The cultivated varieties of watercress

1. Guangdong lobular watercress: leaflet type, plant height 30 cm 40 cm, stem diameter 0.9 cm, 2-3 pairs of leaflets on both sides, apical leaflet oval, 2.6 cm long. It is 2.2 cm wide, brown, and blossoms in late April, but it is not strong and can only reproduce asexually.

2. British watercress: large leaf type, plant height 40 cm 50 cm, stem diameter 0.79 cm, 1-3 pairs of leaflets on both sides, apical leaflet round or nearly round, 3.2 cm long, 3.4 cm wide, green, strong cold tolerance, still do not change color in low temperature and winter.

3. Jiangxi large-leaf watercress: large leaf type, plant height about 40 cm, stem diameter about 0.75 cm, 1-3 pairs of leaflets on both sides, apical leaflet long ovate, 3 cm long, 1.6 cm wide, leaves green, veins red, do not change color in winter and low temperature.

Propagation techniques of watercress

1. Seed propagation: watercress seed propagation mostly sows and raises seedlings when the temperature drops to 20: 25 ℃ from the beginning of September to the end of September, which can be divided into dry land seedling and semi-paddy field seedling. When the seedling height is 4-5 cm, irrigation keeps a thin layer of water on the border surface, and then gradually deepens the water layer to 1.5-2 cm with the growth of seedlings.

2. Cutting propagation: the development of watercress cutting is more than in the middle of September. When the temperature drops to about 25 ℃, the middle and upper part of the tender stem about 15 cm long is cut from the seedling field and transplanted in the pre-ploughed and leveled field for propagation. When the seedling grows as high as 15 cm and 20 cm, the seedlings are planted in the field.

Cultivation techniques of watercress

1. Timely planting: most of the seedlings in the Yangtze River basin are planted in the middle of October, and robust seedlings are selected before planting, requiring thicker stems, short internodes and complete green leaves. The stem of watercress plant is semi-creeping, which is often divided into yin and yang. When planting seedlings, the sun is facing up, and the two basal segments are oblique together with the root system to facilitate survival. The row spacing is 15 cm, the hole spacing is 10 cm, and there are 3 plants in each hole.

2. Soil preparation and fertilization: select paddy fields with low topography, convenient drainage and irrigation, fertile and loose soil, shallow water ploughing and harrowing before planting, combined with ploughing 3000 kg of human feces and urine or 5000 kg of barnyard manure as base fertilizer. After ploughing, rake fine and flat, keep the field muddy or a thin layer of shallow water can be planted. In semi-dryland planting, the land will be leveled and opened after applying basic fertilizer to keep the soil moist.

3. Water management: planting in semi-dry land and watering after planting. At the initial stage, weeds are easy to grow in the field, so weeds should be weeded in time, and then watered every 3-4 days. If the paddy field is planted, it is necessary to maintain a 1-2 cm water layer in the early stage, and then with the growth of the plant, the water level gradually deepens to 3-4 cm, but not more than 5 cm, so as not to cause rust roots.

4. Rational fertilization: watercress can be harvested 30-40 days after planting, and quick-acting fertilizer should be applied in time for each harvest. Generally, 15 kg or 0.5% urea per mu can be foliar sprayed, or 1200 kg of mature manure can be used per mu. After 5 times dilution of water, fertilization should be carried out in the morning and evening.

5. Timely harvest: it can be harvested when the plant height is about 25 cm after planting. There are two kinds of harvesting methods, one is to pick tender shoots one by one and tie them one by one after harvest, which is more labor-consuming. The other is the mud harvest, which cuts off 3/4 of the whole field at a time, steps the old roots into the mud, spreads and rakes flat, and replants the remaining 1/4 seedlings.

6. pest control: watercress has strong adaptability and less diseases and insect pests in cultivation and production. the main pests are aphids, Plutella xylostella, yellow striped beetle, which can be controlled by dimethoate, Bt, dimethoate and so on. Diseases are leaf blight, rust, leaf blight can spray mancozeb or chlorothalonil solution, rust can spray triadimefon solution.