Management of early maturing tomato in spring

The early planting period of early spring tomato depends on the microclimate conditions in the greenhouse. The index is that the ground temperature of 10 cm should be stable above 8 °C, the minimum temperature is above 0 °C (preferably 6-7 °C), and it is stable after 5-7 days. In order to settle in time, it should be shacked in the first 15-20 days before planting, usually in the late March to mid-April. The management after planting is mainly the control of temperature and humidity as well as the management of watering, topdressing and cultivating.
The control of temperature and humidity requires higher temperature after planting, accelerates the slow seedling, and lays a material foundation for flowering and fruit setting. Therefore, 3-4 days after planting, there is no air release, and the shed maintains about 25-30 °C, and the air humidity can reach about 80%. After slowing down the seedlings, reduce the temperature of the shed and increase the amount of air release. 20-25 °C during the day and 13-15 °C at night, but the night temperature should not be too low, otherwise the plant will develop normally and the humidity will drop to about 60%. During the fruit expansion period, the temperature can be appropriately increased, 25-28 ° C during the day, 15-17 ° C during the night, 45%-60% of the air humidity, and 85%-95% of the soil moisture. When the fruit is close to maturity, the temperature of the shed can be slightly increased by 2-3 °C to accelerate the ripening of the fruit. However, it is not suitable for high temperature after hanging the red line, otherwise it will affect the formation of lycopene, which will adversely affect the quality. In order to maintain a suitable temperature, when the minimum temperature at night is not lower than 15 °C, it can be ventilated by day and night.
Watering, top dressing and cultivating seedlings should not only cause high humidity environment, but also prevent the ground temperature from being lowered due to improper watering and affecting the slow seedlings. After the seedlings are slowed down, the seedling water is poured once, and 5-10 kg of urea is applied per acre with water to facilitate the sputum. After the seedling water is used, the seedlings should be carried out, and the watering should be strictly controlled. The soil should be loosened to increase the ground temperature, maintain the soil moisture and achieve the effect of properly controlling the stems and leaves, and promote the accumulation of traits in the body. When the root system grows to the size of the walnut, the seedling should be finished. It is necessary to apply 15 kg of urea per mu or 1000 kg of manure and manure. The water and fertilizer in the fruiting period must be sufficient, and then topdressing 1-2 times. Each time, about 10 kg of urea is applied per mu, or urea or potassium dihydrogen phosphate is used for foliar application. Usually water is poured every 7 days or so. However, the fertilizer should be evenly distributed, and it should not be too big or small. Otherwise, it is prone to empty fruit or umbilical rot.