Seed rate
Approximately 5.0-6.0 kg of seeds are required for cultivating one hectare of land.Soaking seeds in 1:10 solution of 100 ppm Potassium Nitrate for 3 hrs increases germination and seedling vigour.
Planting
January-March and September-December are the ideal seasons for growing bitter gourd. For the rainfed crop, sowing can be started after the receipt of first few showers during May-June. Prepare the soil to a fine tilth by ploughing and harrowing. Pits of 60 cm diameter and 30-45 cm depth are taken at a spacing of 2m x 2m. Well rotten FYM and fertilizers are mixed with topsoil in the pit.
The seeds are soaked in water for 24 hours prior to planting for better and quicker germination. Soaking seeds in a solution of bavistin @ 0.2 % for 6 hours and drying in shade before sowing is also recommended to reduce the attack of soil born fungus. As seedlings require ample water for quicker germination, giving a presowing irrigation 3-4 days before sowing is beneficial. Sow four or five seeds in a pit at 1-2 cm depth. Deeper sowing delays germination. Irrigate with a rose can daily. The seeds will germinate in about 4-5 days. Unhealthy plants are removed after two weeks and retain only three plants per pit.
In high range zone, seedlings can be raised in greenhouses to ensure good germination and are later transplanted to the main field. Sow two or three seeds in small plastic pots/containers filled with potting mixture. Thin to a single seedling at four to six leaf stage. Water the seedlings thoroughly every morning. Seedlings will be ready for transplanting 15-20 days after sowing or when they are 10-15 cm tall. Transplant seedlings into the field at spacings similar to those used for the direct seeding method.