After entering the Beginning of Spring, the vegetable management is busy.

The Beginning of Spring is the beginning of the year's solar terms. At this time, the climate in Beijing is still cold, the temperature is on the low side, there is still snow and sometimes windy weather, but the temperature begins to pick up day by day, and the sunshine hours are gradually prolonged. Therefore, the Beginning of Spring's solar terms in Beijing can be called the prelude to spring. From a meteorological point of view, it still belongs to winter and has not officially entered spring. As the saying goes, "the plan of the year lies in spring" is the busiest time for spring vegetable breeding, soil preparation, planting and solar greenhouse overwintering vegetables management.

? Cultivate strong seedlings

Most spring stubble protected vegetables and some open field vegetables begin to grow seedlings, and the agricultural proverb "half of the seedlings are harvested, the strong seedlings are half and half more" is the importance of cultivating strong seedlings. The seedling raising site is selected in the solar greenhouse or small arch shed. If the ground temperature is lower than 15 ℃, geothermal heating line and temperature controller should be installed to increase the ground temperature.

Cucumber, zucchini, pumpkin, wax gourd, watermelon, melon and other melon crops planted in ◆ melon greenhouse and small arch greenhouse were sown and planted in the first and middle of February and planted in late March. The seedlings were raised with 32 or 50 acupoints or 8 × 8 cm nutrition bowl, and peat and vermiculite were used as substrates. Cucumber varieties such as "Zhongnong 12" and "Beinong Jiaxiu" with early maturity, good quality and strong disease resistance should be selected.

Sowing and raising seedlings of bean and cowpea in early spring in ◆ solar greenhouse, using 50-hole plastic hole tray or 6 × 6 cm nutrition bowl to raise seedlings, sowing 2-3 seeds per hole. The seedlings, which are 15 days old, were planted in mid-late February and harvested in late April.

◆ celery, lettuce spring stubble celery and lettuce were sown and raised seedlings in early February, lettuce was planted in late March, and celery was planted in the first and middle of April. The 128-hole plastic hole plate can also be used to raise seedlings in an ordinary seedbed. Select varieties such as "Ventura" with early maturity and good quality. After soaking the seeds for 24 hours, rub the seeds with hands to remove the substances that inhibit germination, and then sow the seeds evenly after pouring enough moisture.

Management of emergence of ◆

The seedlings of eggplant fruits and melons which were raised in common seedling bed should be divided at 2 leaves and 1 heart stage. Dividing the seedlings into nutrition bowl was beneficial to root growth, and the room temperature was increased by 3 ℃-5 ℃ after seedling division.

Adjust the appropriate temperature to protect against cold and heat preservation, and it is particularly important to maintain the ground temperature. Especially in extreme cold weather, it is important to keep the night temperature not lower than 13 ℃, especially for tomato and cabbage seedlings. Tomato seedlings enter the period of flower bud differentiation after 2 leaves and 1 heart, and malformed fruits are easy to be produced at low temperature below 13 ℃. Cabbage is prone to early bolting at low temperature at 6-leaf stage. Temporary heating measures such as installing Yuba light bulbs, electric heaters and heating combustion blocks should be taken to ensure that the seedlings are not frozen. Temperature-loving crops such as tomatoes and cucumbers should also be separated from cold-tolerant crops such as lettuce and celery in different temperature regions, and the position of the seedling plate should be changed every other week or so to make the seedlings grow evenly.

After increasing the light, we should try to ensure the strong light of the seedlings and make them see more light. Install supplementary light to supplement light artificially, which is beneficial to the cultivation of strong seedlings. The seedlings should be opened for 4-5 hours after planting grass in sunny days and 12 hours in cloudy days.

Timely watering, topdressing and pest control timely watering and topdressing after 2 leaves and 1 heart of seedlings, focusing on the prevention of quenching disease, especially in continuous cloudy days and low temperature and high humidity environment.

? Fertilization and soil preparation in solar greenhouse

As the temperature-loving crops in early spring are about to be planted, it is necessary to fertilize and prepare the soil 15 days in advance, first clean the countryside, reduce the sources of diseases and insect pests, remove the rotten leaves and plastic film of the last stubble in time, and transport them to the designated place for harmless treatment such as ozone disinfection or high-temperature composting. 5000 kg of rotten and fine crushed high-quality organic fertilizer or 3000 kg of bio-organic fertilizer are applied per mu, with a tillage depth of 25-30 cm. Make the ground level and fine, reach the standard of ground leveling, border leveling, and no light and dark bumps, lay drip irrigation pipes, cover with silver-gray plastic film, and wait for the right time to plant.

? Colonization of temperature-loving crops

In the solar greenhouse, temperature-loving crops such as cucumber, tomato, eggplant, pepper and zucchini in early spring began to be planted in the first and middle of February. Generally, the soil temperature of 10 cm can be planted when the ground temperature is more than 15 ℃. In order to improve the quality of soil preparation, enough organic fertilizer should be applied as base fertilizer in advance. Choose the time of "cold tail and warm head" to plant.

? Sowing and transplanting of cold-tolerant and fast-ripening vegetables in greenhouse

Fast-ripening vegetables such as rape, chrysanthemum, spinach, lettuce, Chinese cabbage and cherry radish planted in solar greenhouse are suitable for sowing and planting, and the planting method of sowing and harvesting in batches can be adopted according to the sales situation. Apply 3000 kg of fully mature and finely crushed high-quality organic fertilizer or 2000 kg of bio-organic fertilizer per mu to make fine soil preparation so that the ground is flat, the border is flat, the ridge is straight, and the surface soil is loose without light and dark. Chrysanthemum chrysanthemum, spinach, cherry radish and pakchoi should be planted directly. After pouring enough moisture, sowing evenly, covering the soil with a thin and thick plastic film plays a role in heat preservation and moisturizing, and is removed in time when 50% of the seedlings emerge. Rape, lettuce and celery were transplanted.

? Key period of overwintering vegetable management in greenhouse

Do a good job of heat preservation and cold protection and pay attention to weather changes at any time to prevent strong cold currents and continuous overcast weather from causing damage to crops, and temporary heating measures such as Yuba, heating combustion blocks or electric blast furnaces should be taken if necessary. Scrub the greenhouse film frequently to enhance the light transmittance.

Plant and fruit management timely pruning, branching and falling vines to remove lower old leaves and yellow leaves; auxiliary pollination to remove excess buds, fruits and deformed fruits.

Scientific watering and topdressing should be followed by drip irrigation with comprehensive nutrition, reasonable proportion of "Christmas tree" equal-speed soluble fertilizer, and also with water application of alginic acid or humic acid organic liquid fertilizer with comprehensive nitrogen, phosphorus and potassium content; set up cisterns, tanks or buckets in the greenhouse, watering after the water temperature rises about 18 ℃, but also pay attention to small water watering frequently, vegetables in the greenhouse should avoid flooding.

Timely harvest in the best commodity period, around the Spring Festival is the season of large market demand and high prices. The dishes formed in the Beijing market for many years should not only be fresh and tender, but also look good and tidy, so it is necessary to improve the quality of renovation and improve the value of goods.

The Beginning of Spring's solar terms for pest prevention and control also belong to low-temperature and low-light weather. The low-temperature and high-humidity growing environment in the shed is easy to be infected with diseases and pests such as Botrytis cinerea, sclerotia, downy mildew, late blight and root-knot nematode. It is particularly important to increase temperature and light. On cloudy days, it is also necessary to release air and dehumidify for a short time at noon, and sprinkle a layer of dry sawdust or dry straw between rows to absorb excessive air humidity in the shed. Timely removal of diseased leaves and fruits, placed in designated places for harmless treatment to reduce the source of transmission; selection of low-toxic and low-residue chemicals for timely prevention and control at the initial stage of the disease; more methods of spraying dust agents and smoke fumigation should be used to control diseases and insect pests. Try not to use conventional spraying to reduce humidity in the shed. The regulations of safe harvest interval after application should be strictly observed to ensure the safety of products. Cao Hua