How to Grow Water Spinach in a Greenhouse? Latest Cultivation Technique Tutorial
Water spinach is one of the leafy vegetable varieties that the general public loves to eat. It is produced in large quantities in summer and autumn. In winter and early spring, due to lower temperatures, it is not suitable for its growth. However, in recent years, through experimental cultivation in small arch sheds, film greenhouses and other facilities, success has been achieved, and it can be supplied on the market around the Spring Festival, and good economic benefits have been obtained. Now let us take a look at the greenhouse cultivation techniques for water spinach!
Variety Selection for Water Spinach
Water spinach has two types: seed water spinach and vine water spinach. In the north, seed water spinach, that is, propagation by seed, is mostly used. Generally, the Thai pointed-leaf variety is mainly chosen, and local or Guangxi willow-leaf (pointed-leaf) varieties can also be used for cultivation.
Sowing Methods for Water Spinach
1. Seed soaking and germination: The seed coat of water spinach seeds is thick and hard. If sown directly, germination will be slow due to low temperature. If there is prolonged low-temperature rainy weather, the seeds will rot. Therefore, it is advisable to sow after germination. Soak the seeds in warm water at about 30°C for 18-20 hours, then wrap them in gauze and place them at 30°C to germinate. When 50%-60% of the seeds have sprouted white, sowing can be carried out.
2. Sowing method: Water spinach can be broadcast sown or drilled in rows. The seeding rate per mu is 15-20 kg. After broadcast sowing, cover with fine soil about 1 cm thick. For drilling, dig a shallow trench 2-3 cm deep horizontally every 15 cm on the bed surface, evenly scatter the seeds in the shallow trench, then cover with fine soil, then cover the bed surface with a shade net, pour water, and uncover the shade net after seedlings emerge.
Greenhouse Cultivation of Water Spinach
1. Cultivation season: Greenhouse cultivation can basically achieve year-round production and year-round supply. In order to obtain higher economic benefits, sowing should be arranged from October to December, with harvest from December to March of the following year.
2. Land preparation and fertilization: Water spinach grows quickly and has strong branching ability, requiring more fertilizer and water. When planting, sufficient base fertilizer should be applied. Generally, 1500-2000 kg of decomposed organic fertilizer and 100 kg of plant ash are applied per mu, fully mixed with the soil, and raised into beds 20 cm high and 130-150 cm wide (including trenches).
Greenhouse Management of Water Spinach
1. Temperature and humidity management: During greenhouse cultivation in winter, the temperature is low, the humidity is high, and prolonged low-temperature rainy weather lasts a long time, which is extremely unfavorable to the growth of warm-loving water spinach. Therefore, heat preservation and cold protection are key to off-season cultivation of water spinach. After sowing, when there is sufficient sunlight and the temperature is relatively high, ventilation should be strengthened to remove moisture, and try to avoid the temperature inside the greenhouse exceeding 35°C, to prevent the plants from developing diseases, so as to maintain vigorous growth and increase yield. If low-temperature weather occurs after sowing, the greenhouse should be sealed in time, and the temperature inside should be kept above 10°C, otherwise frost damage will occur. The relative air humidity inside the greenhouse may reach 100% at higher temperatures and on rainy days. At this time, the film at both ends or around the greenhouse must be opened in time for ventilation.
2. Fertilizer and water management: Water spinach is a crop harvested multiple times. Therefore, in addition to applying sufficient base fertilizer, multiple topdressings must be carried out to obtain high yield. During the seedling stage, 10%-15% dilute human manure and urine can be used for drenching, at 1000-1500 kg per mu. When the seedlings have 3-4 true leaves, apply a mixture of 15-20 kg of compound fertilizer and 2-4 kg of urea. During the harvest period, apply topdressing once after each harvest, with 5-8 kg of compound fertilizer per mu. Water spinach has a relatively large water requirement, so it should be watered frequently to keep the bed surface moist.
3. Pest and disease control: The main diseases of greenhouse-cultivated water spinach include damping-off and stem rot during the seedling stage, which are caused by low temperature and excessive relative humidity. Reducing humidity can alleviate the occurrence of diseases. At the same time, 700 times diluted metalaxyl or 800 times diluted kameitong can be sprayed for control. The main insect pests include mites and red spiders, which can be controlled with 1000 times diluted propargite or 1500 times diluted cascade.
4. Timely harvest: Generally 35-45 days after sowing, when the water spinach plants have grown to 35 cm high, they should be harvested in time.