Key points of cultivation and management of broccoli in summer

Broccoli is a 2012 herb, originated in the eastern Mediterranean coastal area, a small amount of cultivation in China, mainly for Western food use. Broccoli is rich in nutrition, containing protein, sugar, fat, vitamins and carotene, ranking first among similar vegetables and known as the "vegetable crown".

Broccoli is a vegetable, a variety of cabbage, broccoli is a cruciferous plant, a leaf broccoli production (20) seed broad, base obtuse, the edge is wavy, smooth glabrous, yellow-and-white flowers of the annual or biennial herbs. Leaves on the root, the main stem and branch stem, the stem is covered with small particles to form a flower, the flower is fleshy, the whole is like a large flower, the color is white and beautiful. Broccoli is tender and delicious, so it is easy to digest and absorb after eating.

Cauliflower has developed root system and strong regeneration ability, so it is suitable for seedling raising and transplanting. It is easy to suffer frost injury below 0 ℃, but it is difficult to form a flower ball above 25 ℃. The growth of foliage and bolting and flowering should be warm and the suitable temperature should be 20-25 ℃. The formation of the bouquet goes through the stage of vernalization at low temperature. Cauliflower is not strict to the light condition, but to the moisture requirement is relatively strict, neither waterlogging nor drought tolerance. It has strong adaptability to soil, but the sandy loam with high organic matter and deep soil layer is the best. The suitable soil pH is 5.5-6.6. The salt tolerance is strong, and it can still grow normally on the soil where the salt content is 0.3% Mel 0.5%.

Key points of cultivation and management of broccoli in summer

First, select improved varieties and sow seeds at the right time

The suitable temperature for broccoli growth is between 16 ℃ and 22 ℃, and the suitable temperature range during vegetative growth period is wide. The average daily temperature during flowering and budding stage is generally below 25 ℃. If the flower bud development period meets high temperature (more than 30 ℃), it will lead to too fast bolting, low yield and poor flower head quality. Therefore, the selection of disease-resistant and heat-resistant varieties and scientific arrangement of sowing time are the key to the success or failure of summer sowing cultivation. Our county generally chooses the precocious and heat-resistant varieties imported from Japan, such as Goldman Sachs, Palu, Pearl Green, etc., and transplants to harvest within 55-65 days; the area with an altitude of 1000-1200 meters is sown from late June to mid-July, and the area with an altitude of 800-1000 meters is sown from mid-July to early August. In order to facilitate harvest and sales, it is best to sow seeds in stages and sow one period in 5-7 days. It will be harvested from late September to mid-November and strive to end the harvest before a large number of coastal products are put on the market, which will help to increase product prices and create better economic benefits.

Second, cultivate strong seedlings and transplant them at the right age.

The cultivation of broccoli in summer is in the high-temperature and rainy season, and the cultivation of strong seedlings is the key. The method of raising seedlings with nutrition bag or nutrient soil mass should be selected. The nutrient bag (or soil mass) is calculated on the basis of 3300 kilograms per 667m2 in the field, and its formula is 60000kg of fertile paddy soil, 30kg of grain hull ash, 80kg of fermented pig manure, 0.5kg of imported compound fertilizer (preferably N:P:K=21:6:13 's compound fertilizer containing potassium sulfate), 3kg of calcium magnesium phosphorus and 2kg of lime powder. The soil was disinfected with 450 times solution of 15% carbendazim (or pentachloronitrobenzene), stirred evenly, covered with plastic film and sealed for about 10 days. Before sowing, put a seedling bag of 8cm × 10cm into nutritious soil (or printed into a nutritious soil mass), then sow 1 seed for each soil bag (or soil mass), cover the seed with sifted fire and burn soil fertilizer, and build a greenhouse to cover it with a sunshade net with a sunshade rate of 65%. The management of fertilizer and water should be strengthened at the seedling stage, and the seedling age should be 25-30 days (4 leaves, 1 heart ~ 5 leaves and 1 heart).

Third, select land for deep ploughing and apply sufficient basic fertilizer

According to the growth characteristics of broccoli and its requirements for environmental conditions, paddy soil with an altitude of more than 800m, deep soil layer, high content of organic matter, good drainage and irrigation conditions, strong water and fertility conservation and moderate sand viscosity should be selected. Do not choose the former fields for planting cabbage. Most of the soils in southern mountainous areas are highly acidic. About one month before planting, 100kg / mu of lime powder should be applied, combined with deep turning and tanning, and the thickness of deep ploughing is between 30cm and 35cm. The whole layer of base fertilizer was applied 10-15 days before transplanting, with 1000-13000 kg of fermented pig manure and 120-200 kg of plant ash per mu, or 500-600 kg of imported ternary compound fertilizer containing potassium sulfate and 200-300 kg of calcium, magnesium and phosphorus. Broccoli has a great demand for trace element boron, so no matter using chemical fertilizer or organic fertilizer as base fertilizer, 2 kg of borax should be applied per mu to meet the needs of its growth and development.

IV. High border cultivation and reasonable close planting

Broccoli is a kind of crop that likes temperature and light but is afraid of heat, moisture and impregnation. In order to improve the utilization rate of light energy, increase soil permeability and improve the field microclimate, high border cultivation and reasonable close planting should be emphasized. Especially in the southern mountainous areas, the annual rainfall reaches 1800mm to 2000mm, so it is of special significance to adopt deep trench and high border cultivation. In general, the width of the border belt ditch is 1.1 to 1.2 meters, and the border height is 25 to 30 centimeters. The surrounding drainage ditch and the waist trench in the field are required to be 50 to 60 centimeters deep, so that the ditches communicate with each other and are easy to irrigate and drain. Goldman Sachs, Balu and Pearl Green are all early-maturing varieties of broccoli, which are conducive to close planting, with a general plant spacing of 50 cm to 60 cm and a row spacing of 35 cm to 40 cm, planting 2800 plants per mu. When transplanting seedlings with nutrition bags, we should carefully tear off the nutrition bags and adopt the method of transplanting shallow holes, which is 5cm deep and 8cm deep, so that the ventilation at the base of the stem is poor and it is easy to induce blight.

V. strengthening field management

1. Reasonable topdressing of broccoli should be carried out for 4 times. After transplanting, the fertilizer can be irrigated with 10%-15% rare manure and urine, and the second and third times are carried out at 15-18 days and 25-28 days after transplanting, respectively, with urea 5-6 kg per mu and potassium chloride 4 kg per mu. The fourth time was carried out 37-40 days after transplanting, when it had entered the rosette stage, which was about to show buds. It was necessary to re-apply budding fertilizer in time to promote the rapid growth of flower buds. 20 kg of potassium sulfate compound fertilizer could be used per mu. Deep application was made at 15-20 cm from the base of the stem (it has been closed and inconvenient to be applied). After application, the soil was covered in time, and the soil was irrigated to make the fertilizer dissolve and absorb. In order to promote the robust growth of the plant and improve the rate of finished flower heads, foliar fertilizers such as double-effect micro-fertilizer, spray Shibao and plant power 2003 can be selected and sprayed once in seedling stage, vigorous growth stage and budding stage.

2. Scientifically irrigated broccoli should be watered to protect seedlings after transplanting, and sunshade should be covered if possible to improve the survival rate. The proper control of water after survival is beneficial to the deep root system. The water demand in the middle and later period of growth is large, and the water evaporates quickly in summer. In case of drought, water should be watered every evening, or horse race water should be irrigated once every 3 days to keep the soil moist, and the border should be covered with straw or weeds to reduce water evaporation. At the same time, typhoon rainstorm is frequent from July to September, so it is necessary to clear the ditch and drain in time to meet the requirement that there is no stagnant water in the ditch.

3. The broccoli should be ploughed for 1 or 2 times before the row closure. After the row closure, the broccoli should no longer be ploughed, but some weeds should be pulled out by hand. After typhoon and rainstorm, the soil should be loosened in time to prevent soil consolidation, increase soil permeability and promote root growth. Shallow hoe is the main method to loosen the soil, and be careful not to hoe the root system.

VI. Timely prevention and control of diseases and insect pests

1. Quenching disease and blight disease are the main diseases in seedling stage. 58% metalaxyl manganese zinc 500 times solution or 64% poison alum 500 times solution can be used to control the disease. The blight disease can be treated with 1200 times of 20% methyl trimethophos EC or 45 times of 15% chlorpromazine water, or 1000 times of 70% dimethazone.

2. Bacterial soft rot, black rot and black spot belong to bacterial diseases, which are also the main diseases in out-of-season cultivation, which should be controlled in time. The flower buds began to differentiate into the susceptible stage, and 75% agricultural streptomycin was sprayed with 1000 times of agricultural streptomycin at the initial stage of the disease. When the disease was serious, the above drugs were used alternately, sprayed once every 5-7 days, and used continuously for 2-3 times. The disease can be effectively controlled.

3. Pest control mainly includes aphids, Plutella xylostella, Plutella xylostella, Plutella xylostella and so on. We can choose biological pesticide Bt500~800 multiple solution (when the population density is high, a small amount of pyrethroid pesticides can be added, but can not be mixed with fungicides), or spray control with 1000 times of 40% Lexben, 2000 times of 2.5% cypermethrin EC, and 3000 times of 21% killing.