(1) The seedlings should be virus-free, high-quality and robust. The standard of strong seedlings should be developed root system, 4-5 mature leaves, normal petiole leaf color, full central bud, new stem diameter greater than 65438±0cm, thick white fibrous roots, uniform distribution and stretching, seedling weight of 20-30g, early flower bud differentiation, good development and no diseases and insect pests.
(2) Soil treatment ① Soil disinfection. Strawberries are not suitable for stubble, but it is difficult to stubble in greenhouse. In order to reduce diseases, strict disinfection should be carried out before planting. It can be disinfected with solar energy or fumigated with chemicals. ② Applying base fertilizer. Strawberry has long fruiting period, high yield and great demand for nutrients. It is very important for strawberry to apply base fertilizer for high quality and high yield. Generally, more than 5000 kilograms of decomposed high-quality organic fertilizer is applied per mu. In addition, 50 kg of strawberry special fertilizer or NPK compound fertilizer is added to the base fertilizer. After the base fertilizer is spread evenly, plough it for 2 ~ 3 times to fully mix the soil and fertilizer, till the depth is about 30cm, and then ridging.
(3) The planting time is generally from late August to early September, and the natural air temperature 15 ~ 20℃ and the ground temperature 15 ~ 17℃ should not be too late, otherwise it is not conducive to the growth after delayed seedling.
(4) Planting method ① Sowing. Before planting, the nursery should be watered once for 1 ~ 2 days, which is beneficial to take good soil and reduce root damage. Planting should be carried out in sheds according to the size of seedlings. If the seedlings are raised in nutrient pots, the plastic pots should be removed when planting, and the survival rate is higher. ② Planting density. Greenhouse cultivation generally adopts large ridges and double rows. Generally, the ridge height is 30 ~ 40 cm, the upper width is 50 ~ 60 cm, the lower width is 70 ~ 80 cm, the ditch width is 20cm, the plant spacing 15 ~ 20 cm, and 7000 ~ 9000 plants are planted per mu (the planting density can be determined according to the variety characteristics). When planting, the arch back of strawberry seedlings is required to face outside the border (ditch) for planting. ③ Planting depth. The planting depth must be appropriate, deep without burying the heart and shallow without exposing the roots. The base of the new stem must be buried in the soil to facilitate the generation of new roots, but the center of the seedling (a little part of the outer leaf stipules) cannot be buried in the soil, so it is particularly important to pay attention to that the weak seedlings cannot survive when planting, otherwise it is easy to die. ④ Post-planting management. Immediately after planting, water should be poured along the ditch, and it must be thoroughly poured to keep the soil moist. After delaying emergence, new leaves spread out and began to grow vigorously. During this period, as long as the soil is dry, there is no need to water it until the end of September. In order to promote flower bud development, it is necessary to strengthen fertilizer and water management, topdressing urea 10kg per mu, watering after topdressing, and watering every 5 ~ 7 days. At the same time, old leaves and diseased leaves should be removed at any time, and the stolons that have been removed should also be removed. If the seedlings grow too vigorously and have too many leaves before heat preservation, they should also pick leaves and leave 5 ~ 6 leaves. When picking leaves, remove side buds to reduce nutrient consumption.
2. Temperature and humidity adjustment
2. 1 temperature regulation
(1) Temperature requirements in each climate period ① Early heat preservation in the shed. Maintain 28 ~ 30℃ during the day, and ventilate if it exceeds 30℃; Keep 12 ~ 15℃ at night, not lower than 8℃. When the outside temperature is high at the initial stage of heat preservation, it is not necessary to cover the insulation quilt temporarily, and attention should be paid to cooling during the day, and then cover the semi-insulation quilt or full insulation quilt according to the cooling situation. ② Germination stage. Maintain 25 ~ 28℃ during the day; Keep it at 10 ~ 12℃ at night, and the temperature at night should not be higher than 13℃, otherwise it will affect the development of axillary buds and hinder the development of flower organs. ③ flowering period. The flowering period has strict requirements on temperature, and it is kept at 23 ~ 25℃ during the day. Maintain 8 ~ 10℃ at night. (4) fruit expansion period. Maintain 20 ~ 25℃ during the day; Keep 5 ~ 8℃ at night. When the temperature is above 10℃ at night, plants consume more nutrients and fruit expansion is affected. ⑤ Fruit harvesting period. Maintain 20 ~ 25℃ during the day; Keep 5 ~ 8℃ at night.
(2) Heat preservation measures ① Cover the shed film. At night, when the outdoor temperature drops to 8 ~ 10℃, heat preservation will be started, and the first ten days of 10 will be the suitable period for heat preservation (the suitable period for shacking). Premature heat preservation and high indoor temperature are not conducive to axillary flower bud differentiation; Too late, plants hibernate, resulting in short plants, which is not conducive to normal results. It is best to use PVC long-life drip-free film with good light transmittance to increase the light intensity in the greenhouse. ② Covered with plastic film. Black plastic film is generally selected. Laying black plastic film can keep soil moisture, inhibit the growth of weeds, reduce the air temperature in the greenhouse, isolate the contact between strawberry fruit and soil, reduce diseases, and keep the fruit bright, clean and hygienic. The laying time of black plastic film is generally 10 ~ 15 days after the tent buckle. At this time, all strawberries have survived, and weeding, loosening soil, bacon and replanting have been initially completed. The laying method is to cover the ridge planting plants with black plastic film, tear a small hole in the plastic film when touching the seedlings, and then carefully pull out the leaves. Be sure to expose the leaves in the center of the seedling, and the old leaves around will press the edge of the plastic film hole on the plastic film.
(3) The way of temperature adjustment mainly depends on fresh air, that is, the temperature is adjusted by the size of fresh air outlet and fresh air time. Generally, when the outdoor temperature is low and the indoor temperature needs to be raised, the air outlet should be small and the air release time should be short; When the outside temperature is high and it is necessary to reduce the indoor temperature, the air outlet should be larger and the air release time should be longer. In addition, the air outlet should be gradually opened in stages to avoid sudden exhaust and seedling injury.
The key period of the transition from high temperature management to low temperature management after plant budding. At the same time of cooling, the humidity in the shed is also rapidly reduced due to the outdoor air, and the leaves are easy to lose water and dry up, and even the buds are damaged in severe cases. All temperature changes should be gradual, the cooling can last for about 3 days, and the leaves should be sprayed with water twice during the day.