Cultivation Methods for Water Chestnut (Water Caltrop) in Greenhouses, Harvest Time, and Yield per Mu

Water chestnut, also known as water chestnut and water caltrop fruit, is a common aquatic plant in southern China. It is widely cultivated because it can be eaten as a fruit when young and tender and made into water chestnut flour when mature. At present, many regions are also trying to cultivate it in greenhouses. So how do you cultivate water chestnut in a greenhouse? When do you harvest it? About how many jin can be produced per mu?

1. When are water chestnuts harvested? About how many jin can be produced per mu?

For open-field cultivation of water chestnut, the harvest time is from August to October, and the yield per mu is 2000-3000 jin; for greenhouse cultivation of water chestnut, the harvest time is from mid-May to November, and the yield per mu is 5000-6000 jin.

High-yield cultivation techniques for greenhouse water chestnut:

2. How are greenhouse water chestnuts cultivated?

1. During the seedling stage of greenhouse water chestnut, the water layer should be kept stable; otherwise, the growth of the water chestnut seedlings will be affected. According to the production target of 1.5 t/667 sq m of fresh water chestnut, apply 15 kg/667 sq m of ternary sulfur-based compound fertilizer (15-15-15), spread it, and then transplant.

2. During the peak tillering stage, thin the mats in time, leaving 15-20 mats per sq m. Later, during harvesting, also remove weak and small mats at any time so that the number of mats remains at 15-20 per sq m, and cultivate robust mats with a diameter of more than 30 cm to prevent the mats from covering the water surface too early, which would result in small mats and affect yield. Topdressing should be carried out in multiple applications.

3. At the early flowering stage (about 45 d after transplanting), apply 10 kg/667 sq m of compound fertilizer. After that, immediately after each water chestnut harvest, alternately apply 5-8 kg/667 sq m of Jiamei Yinglilai or 10 kg/667 sq m of compound fertilizer. After the 3rd harvest, remove about 40% of the mats to thin the pond, and after thinning, apply 15 kg/667 sq m of ternary compound fertilizer.

When topdressing, gently push aside the mats with your foot at intervals of about 2 m, then take 1 handful of fertilizer and apply it into the water. Starting at early flowering, spray 800-fold Jiamei Brain Platinum or Jindian on sunny days from 7:00-8:00 or 17:00-18:00, combined with pest control spraying.

4. At the full flowering stage (that is, when each mat has 3-4 water chestnuts), use paclobutrazol for chemical regulation, which has a significant effect on increasing the fruit-setting rate of water chestnut. In water chestnut fields, pay attention to changing the water frequently and maintaining air circulation. Generally, change the water at around 6:00 and maintain a water layer of 20-30 cm. In summer, when the temperature is high, the water layer should be kept above 30 cm.

5. The field must be level; uneven height easily breeds weeds. Water chestnut is sensitive to herbicides. Once weeds are found, carry out manual pulling as early as possible.

6. At this stage, focus on managing moss in the greenhouse, control the damage of golden apple snails, and promptly remove four-leaf clover manually to prevent its spread; otherwise, it will affect the photosynthesis of water chestnut. At the same time, reasonably control the greenhouse temperature and ventilate in time. In the morning, when the greenhouse temperature rises above 20°C, roll up the film roller to facilitate ventilation and cooling, keep the temperature at 20-30°C, and lower the film roller at around 15:00 to preserve heat.

7. In June, when the temperature is slightly higher, tie up the greenhouse skirt film with rope to facilitate ventilation and cooling. After the plum rain period passes, remove the greenhouse film to prevent unstable temperatures and heavy rain from washing the mats, which is unfavorable for flowering and fruiting.

8. Pest and disease control: The main diseases are water chestnut blast and water chestnut brown spot. Attention should be paid to reasonable close planting, maintaining water circulation, and preventing pollution. Spray with 750-fold 20% tricyclazole solution or 600-fold 50% carbendazim solution for control.

The main insect pests are flea beetles, leafhoppers, and aphids that damage the mats. Spray with 1000-fold 25% beta-cypermethrin, and control 2-4 times depending on the occurrence of the pests. According to the practice of cultivating water chestnut in recent years, to obtain high yield, pest and disease management must be done well, reducing the occurrence of water chestnut pests and diseases, and allowing water chestnut to grow efficiently!