Water tomato seedlings in time (1) Temperature management The temperature management of tomato seedlings should master three highs and three lows: that is, the temperature before or after emergence should be high, and the temperature before seedling separation after emergence should be low; The temperature should be high during the day and low at night; The temperature is higher in sunny days and lower in rainy days. After sowing, the daily temperature is 28 ~ 30℃, the night temperature is 24℃, and the bed soil temperature is 20 ~ 25℃, which is beneficial to seedling emergence. After the seedlings are fully grown, the bed temperature should be reduced to 20 ~ 25℃ during the day and to 17 ~ 18℃ at night. Ventilation is mainly used, with small wind first, then amplified wind, and slow cooling. The first true leaf is the growth stage of the seedling before seedling division. It is necessary to create good conditions, keep the ground temperature above 15 ~ 20℃, and promote the root system development. After seedling sorting, the daytime temperature is 25 ~ 28℃, at night 18℃, and the ground temperature 15 ~ 20℃. Foliar fertilization can make seedlings grow new roots as soon as possible and accelerate seedling delay. After slow sowing, the temperature is controlled at 20 ~ 25℃ during the day and 12 ~ 15℃ at night. The flower bud differentiation period of seedlings is 1 week after seedling division and before planting. Using variable temperature treatment can ensure the quality of flower bud differentiation, promote growth and prevent excessive growth. The specific methods are: 25 ~ 27℃ in the morning, 20 ~ 25℃ in the afternoon, 14 ~ 17℃ in the first half of the night, 12 ~ 13℃ in the second half of the night, and the temperature difference between day and night is 5 ~ 8℃. Low-temperature exercise is started 1 week before sowing, and it can reach 7 ~ 8℃ at night, which enhances the cold resistance of seedlings.

(2) Water management at seedling stage Tomato seedlings have developed roots, strong water absorption and easy to grow in vain, so the amount of watering tomato seedlings should be small and the watering times should be less. Pay attention to water control, focusing on water control, combining promotion and control, keeping the seedbed dry and wet, and ensuring air humidity of 50% ~ 60% and soil humidity of 75% ~ 80% on sunny days; On cloudy days, the air humidity is ` 50% ~ 55% and the soil humidity is 60% ~ 65%.

(3) Besides proper amount of organic fertilizer, quick-acting fertilizer should also be applied in seedling nutrition management. In addition to nitrogen fertilizer, pay attention to using a small amount of phosphorus and potassium fertilizer. During the 30 ~ 40 days of seedling growth, topdressing outside the roots once every 65438 00 days, using 2% calcium superphosphate solution or 0? 1%~0? Spraying 2% potassium dihydrogen phosphate solution on the leaves.