1, 1 Select fine varieties.

Daji, Jingnan and other places in our county have the unique conditions of "no heat in summer and cool climate", and the harm of pests and diseases is light. In the selection of improved varieties, we mainly choose varieties that are moisture-resistant, high-temperature-resistant, disease-resistant, high-yield and mature. Qingnong 65 and Qingnong 85 are generally chosen as the main varieties.

1 2 Sow in time

Qingnong 85 should be planted in mid-March when it is planted at the altitude of 1000m, and the seedlings should be raised in a small arch shed. Qingnong 65 should be sown from late February to early March, and raised in a small arch greenhouse.

Cultivate strong seedlings

Cultivating strong seedlings is the basis of high and stable yield. In order to cultivate vegetable seedlings into strong seedlings, greenhouses or small arch sheds should be used in cold areas. First, we should choose a field sheltered from the wind and sun as a seedbed, and secondly, we should prepare nutritious soil. Generally, 70% of pollution-free fertile soil in 100 kg of nutrient soil, 10% of plant ash, 20% of decomposed organic fertilizer and 1 kg of urea can be used as a nutrient bowl and sown with water. Generally, sow three seeds in a bowl and cover them with fine soil after sowing. And do a good job in thinning seedling management and pest control to ensure the whole seedling and cultivate strong seedlings.

Land consolidation and border preparation

Pine cabbage should be planted in fields with loose and fertile soil and convenient irrigation and drainage. Before ploughing, borax 1kg, 60kg of quicklime and 50g of ammonium molybdate were applied as base fertilizers every 667h2. After ploughing, decomposed organic fertilizer 1000kg, calcium magnesium phosphate fertilizer 30kg, compound fertilizer 30kg and potassium fertilizer 20kg were applied as base fertilizers every 667h2. A deep border with a width of 1- 1.3m and a depth of 0.3m was made for planting.

Timely planting and reasonable close planting

Qingnong 85 and Qingnong 65 can be planted when the seedling age reaches 30-35 days. Generally, two rows are planted in each border, with a row spacing of 50-70 cm and a plant spacing of 45-65 cm. 65 Qingnong plants 1700 plants/667m2; Qingnong 85 should be planted per 667m2 1300 plants. The density with good soil fertility can be thinner, otherwise it can be denser.

Insect disease prevention

The main pests and diseases planted in Gaohaibo area of our county are aphids, caterpillars, black root disease, root rot and so on. Use 3000-5000 times of 25% imidacloprid wettable powder and 3000 times of 15% Anta suspension to control aphids and caterpillars. In order to control black root disease and root rot, 800- 100 times of 75% chlorothalonil wettable powder and 600- 1000 times of genfuling wettable powder were used to irrigate roots once every 7 days and twice in succession, which can achieve good control effect.

Tiantuan management

1, scientific fertilization

The principle of fertilization in the whole growth period of Chinese cabbage is that "nitrogen fertilizer is the main fertilizer in the early stage, phosphorus and potassium fertilizer are applied in the middle stage, and topdressing outside the roots is appropriate in the middle and late stage". Generally, nitrogen fertilizer is the main fertilizer at seedling stage, and thin fertilizer can be applied frequently to promote rosette leaves. It is the peak period for Chinese cabbage to absorb fertilizer before and after germination, and phosphorus and potassium fertilizers should be the main ones. Generally, 20 kg of compound fertilizer should be applied to 667h2? Promote the development and growth of the flower ball. Some trace elements can be added in the middle and late stage (before and after budding). Generally, 0.2% borax +0.2% potassium dihydrogen phosphate +0.2% urea can be used as topdressing outside the roots, which has a positive effect on promoting flower head expansion and whiteness.

Step 2 raise the soil

Through the cultivation of soil, Chinese cabbage can promote the growth of adventitious roots, stabilize the soil environment for root growth, and enhance the growth, lodging resistance and stress resistance of plants. Generally speaking, it is better to combine soil tillage for 2-3 times when fertilizing, weeding and loosening soil.

3. Scientific water management

Chinese cabbage needs a lot of water, so the soil in the field should be kept moist during the whole growth period, especially in the period of clumping and flower ball formation, which are the two peak periods of water demand, and at this time, the field should keep enough water. In case of drought, "Happy Horse Racing Water" should be irrigated in time. Do a good job of ditch cleaning and drainage in rainy days to prevent water accumulation in vegetable fields from affecting growth.

Bundle leaves to protect flowers

The flower head of Chinese cabbage will turn yellow in the sun, which will not only affect the goods, but also affect the fresh and tender quality of the flower head. Therefore, the maintenance of flower heads is an important link in the production of Chinese cabbage. In order to prevent the quality of flower balls from being affected by sunlight, flower protection method should be adopted. The specific method is: when the flower ball grows to 10cm, 4-5 leaves near the flower ball are overlapped and fixed tightly at one time, so that the flower ball is not exposed to sunlight, grows white and tender, and improves the quality and commodity.

Source: China Organic Agriculture Network