Planting technology of cabbage in greenhouse

Kale is not only one of the most important vegetables in China, but also one of the best vegetables recommended by the World Health Organization, also known as lotus white, cabbage, cabbage and cabbage.

Soil preparation and fertilization

Cabbage planting in greenhouse generally applies 5000 kg of rotten farm manure and 50 kg of medium nitrogen, high potassium and low phosphorus compound fertilizer per mu. In order to improve quality and stress resistance, high quality calcium fertilizer can be combined with high quality calcium fertilizer to prevent dry heartburn. Spread fertilizer evenly over the field, plough and rake flat to make beds.

Timely planting

Cabbage planting in greenhouse is generally completed before the end of March, planting too late, the advantages of early listing of protected land can not be brought into full play, the economic benefit is not high, it loses the significance of early cultivation. In general, the density of early and middle maturity varieties is 2500 to 2800 per mu, the density is too high, the weight per plant is decreased, and the density is too low, the overall yield will also decrease. Choose to plant in sunny and high temperature weather for 3-5 days in a row, and the amount of water per plant should not be too large after planting.

Field management

Cabbage is a semi-low-temperature-tolerant vegetable. Cabbage needs a higher temperature when planting slow seedlings. The temperature in the greenhouse is 25: 28 ℃ in the daytime and no less than 10 ℃ at night, in order to promote the rapid growth of root system. Usually the seedlings can be slowed down after three or five days. Then enter the squatting seedling stage, properly lower the temperature, keep it at 20: 25 ℃ during the day, control the amount of water, squatting seedlings for about 10 days. Enter the rosette stage, according to soil moisture and seedling growth, irrigate small water and apply 15kg urea to promote the rapid growth of leaves. When entering the heading period, there is a great demand for phosphate fertilizer and potash fertilizer, and there is a great demand for water. It is necessary to apply 20 kg phosphate and potash fertilizer. It is better to see dry and wet in the field, and it is not suitable to pour heavy water. The temperature during the heading period should not be too high, and the air discharge should be gradually increased according to the increase of the external temperature, and the maximum amount of air release should not exceed 28 ℃ in the daytime.

Prevention and control of diseases

Due to the high humidity of the growing environment, two diseases often occur in cabbage production, namely downy mildew and black rot. The disease of cabbage downy mildew is that there are yellow polygonal irregular spots on the front of the leaves, serious perforation and a gray mildew layer on the back. Generally high incidence in the mid-heading high-humidity environment, you can choose silver in the initial prevention and treatment, continuous use of drugs twice. Black rot to root base leaf rot, there is a bad smell, there is a black plate, you can choose Wanjia spray twice.

Timely harvest

The harvest time of cabbage in greenhouse is generally at the end of April and early May. When the top of the leaf ball of cabbage is flattened and the leaf ball is tight, it can be harvested. Precocious varieties generally have a net weight of 1-1.5 kg per ball. Two or three old leaves are retained in the lower part of the bulb during harvest to protect the bulb, prevent extrusion and mechanical damage during transportation, and improve the commerciality of the bulb.