1. Cultivation season: Sowing in the Yangtze River Basin is mostly done in April and harvested from September to October.
2. Cultivation technology
(1) Choose a good water surface and apply sufficient base fertilizer: Choose a water surface with a depth of 1 to 3 meters, fresh water quality, fertile subsoil, and small water level changes. Before planting, Remove aquatic plants, wild water chestnuts, moss, etc. and apply sufficient base fertilizer. Generally, 1,500 to 3,000 kilograms of decomposed manure, 1,000 kilograms of human excrement, 10 kilograms of urea, 25 kilograms of superphosphate, and 6 to 8 kilograms of potassium chloride are applied per mu. The applied fertilizers should be fully mixed with river mud to reduce loss.
(2) Sowing or seedling transplanting: The cultivation of water chestnut can be carried out by direct seeding, or the seedlings can be cultivated first and then transplanted. There are two types of live broadcast: broadcast and drill broadcast. The spacing between drill rows is 2 to 3 meters, and the seeds are sown evenly according to the rows. During sowing, poles and ropes are set up on the water surface to mark sections, and water chestnuts are placed on boats. 5 to 6 water chestnuts are sown per meter. In some places, drill sowing is changed to hole sowing, that is, waste newspapers are used to paste into small bags, filled with nutritious soil and 3 diamond seeds, and one bag is sown per meter. The amount of seed used per acre of water surface is 18 to 20 kilograms, and the amount of seed used for broadcasting is larger, about 20 to 25 kilograms.
The transplanting of seedlings should be carried out 10 to 20 days earlier than the normal sowing date. Choose a pond with shallow water, soil and fertilizer, and convenient drainage and irrigation. The row spacing is 15 cm × 10 cm square, and one seed is sown in each hole. 70 to 100 kilograms of water chestnuts can be sown per acre and can be transplanted into 7 to 10 acres. Start by maintaining a 10 cm water layer. After germination and rooting, the water layer gradually deepens as the water chestnut seedlings grow. Before and after the awns are planted, the water chestnut seedlings grow to about 50 cm, and when the water chestnut leaves cover the pond, they can be transplanted. Late maturing species should be transplanted after Xiaoshu at the latest. The appropriate planting density is 500 to 800 plants per acre.