First, seedling management: seedling management can be divided into three stages:

1, the first stage: sowing until the soil is bare. At this stage, there is generally no ventilation, and the bed temperature and humidity are kept high to promote its rapid germination and emergence. At this time, the temperature is about 30℃ and the soil temperature is 25-30℃.

2. The second stage: 60%-70% seedlings emerge until the first cotyledon is exposed. At this stage, hypocotyl is the easiest to grow in white, so it is necessary to properly ventilate, reduce the bed temperature and control the moisture of the seedbed. The bed temperature can be reduced to 25-28℃ during the day and to 12- 15℃ at night. At this stage, we should extend the light as much as possible to promote the seedlings to be strong, but we should not stay in strong light and high temperature for a long time, and shade them in case of high temperature.

3. The third stage: hardening the seedlings before transplanting, keeping the temperature at 20-25℃ during the day and 10- 12℃ at night.

Second, colonization.

When planting tomatoes, the minimum temperature in the protected field should be above 10℃, and the soil temperature of 10 cm should be stable above 15℃.

(1) Soil preparation, soil preparation: mix the spare base fertilizer evenly, spread it on the ground, turn the soil 30-40 cm deep and level off.

(2) Planting density: It is generally appropriate to use root control devices to cultivate tomatoes in protected fields. The diameter of the pot is 25-30 cm, the spacing between plants is 30 cm, and there are 4000-4500 plants per mu.

(3) Planting: Choose sunny days with no wind when planting tomatoes, make full use of sunlight, improve the soil temperature in the planting border, and promote the rapid recovery of seedlings. The planting depth of tomatoes should be flush with the ground.

(4) Watering: 5-7 days before planting, water the whole bed surface once, then close the whole shed, and open the air outlet of the shed the day before planting to prepare for planting. Generally, seedlings are planted first and then watered. Should be thoroughly watered, no water. After planting, water the holes with planting water, water the seedlings again after 3-5 days, and then transfer to squatting seedlings.

Third, on-site management

(1) temperature management

1. Before planting: At this time, the temperature should be high, especially the ground temperature. Before slow planting, the temperature should generally not exceed 30℃, and it is not necessary to release air, and it is appropriate to be around 28℃.

2. The growing season is 24-26℃ during the day, 8℃- 10℃ at night, and about 13℃ in winter and spring.

3. fruiting period: the temperature is slightly higher than that after slow seedling. At 25-26℃ during the day, air is released above 25℃, and the tuyere is closed at 20℃; At night, it is 13- 15℃, and the lowest temperature from midnight to the next morning can be controlled at 10- 13℃, and the ground temperature is not lower than 15℃. (Automatic ventilator is recommended for temperature control, which can accurately control the temperature in the shed and save labor costs. )

(b) fertilizer and water management

Tomatoes are very sensitive to soil moisture. Water imbalance will cause navel rot, too much water will cause vain growth, and insufficient water will affect the growth of plants and fruits. Therefore, the irrigation quantity and irrigation cycle should be strictly controlled. Its principles are: no watering on cloudy days, light irrigation at seedling stage, thorough irrigation at planting stage, no watering before flowering, light irrigation at flowering stage and light irrigation at fruiting stage.

1. water: during the slow growth of seedlings, the humidity should not be too high to prevent improper watering, reduce the ground temperature and affect the slow growth of seedlings. After slow seedling, water the slow seedling once. After watering the slow seedlings, squat the seedlings and strictly control watering. Loosening soil in Qin Ying can raise ground temperature and keep soil moisture, so as to properly control the overgrowth of stems and leaves, promote the accumulation of plant substances and coordinate the relationship between vegetative growth and reproductive growth.

2. Fertilizer: potash fertilizer is the main topdressing, with nitrogen fertilizer, phosphorus fertilizer and foliar micro-fertilizer. If the soil is fertile and the base fertilizer is sufficient, a small amount of topdressing can be applied during the growth period, and the amount of "Woye Ion" potassium dihydrogen phosphate is sprayed on the leaves at 0. 15kg per mu, once in mid-February and early March respectively. In order to reduce the humidity in the shed, drip irrigation system can be used when supplying water (which can reduce the humidity in the shed), which can greatly reduce the occurrence of pests and diseases in the shed.