Broccoli Cultivation Techniques and the Ratooning Method Explained in Detail, with a Bonus Method for Preventing and Controlling Edible Fungus Diseases
Broccoli is an annual or biennial herbaceous plant native to the eastern Mediterranean coastal region. It is now cultivated in both northern and southern China and has become one of the main everyday vegetables. The Agricultural Knowledge Network now introduces broccoli cultivation techniques and the ratooning method as follows. Broccoli Cultivation Techniques and the Ratooning Method
1. Land preparation and fertilization: Broccoli requires relatively abundant and complete nutrients, but its root system penetrates the soil rather shallowly. Therefore, it should be planted in fertile soil that retains water and nutrients well. Pay attention to applying base fertilizer; generally, per 667 sq m (1 mu), use 100 kg of organic fertilizer, 10 kg of urea, 25 kg of compound fertilizer (15% each of nitrogen, phosphorus and potassium), and 2 kg of borax as base fertilizer. Plow the land, harrow it level, open furrows and apply fertilizer, with the furrow-to-furrow width being 50-70 cm in wide and narrow rows.
2. Seedling raising and transplanting: The sowing period for broccoli depends on the characteristics of the variety, the length of the growth period, and the climate and environmental conditions of the planting region. In the Qingdao area, spring sowing is generally from late January to early February. For spring greenhouse seedling raising, use double-layer film; at emergence, the ground temperature should be 25°C, and after emergence the greenhouse temperature should be 18-20°C. The seeding rate is about 15 g per 667 sq m, sown as single seeds, and the seedling age is about 40 days. When the seedlings have 4-5 leaves, begin establishing them in the field, where small arched sheds are needed. For autumn sowing, raise seedlings in the open field in early July, cover with a shade net after sowing, remove the shade net promptly once the seedlings emerge, and spray pesticides to prevent damping-off disease and soil-dwelling pests. For autumn seedling raising, the seeding rate can be slightly higher than in spring. When the seedlings are 25 days old and have 4 leaves and 1 heart leaf, they can be transplanted to the field. As for planting density, 2700-3000 plants per mu in spring and 2000-2500 plants per mu in autumn, and water once with settling water at planting time.
3. Field management:
(1) In spring, broccoli should be ventilated by opening holes according to weather changes, or the small arched sheds should be removed. After removing the film, weed promptly, spray pesticides to prevent insects and treat diseases as the situation requires, and carry out topdressing. Generally, apply 40 kg of ammonium sulfate and 10 kg of potassium fertilizer per 667 sq m as topdressing.
(2) After planting autumn broccoli, water thoroughly once promptly to help the seedlings recover, and weed on time; in the mid-term, carry out topdressing in combination with intertillage. Open furrows and earth up around the roots to prevent drought and waterlogging, and observe carefully, promptly prevent and control pests and diseases, and promptly prune and remove side branches. Removing thin, weak side branches can save nutrients for the growth of the main stem's curd.
4. Time management and harvesting for ratooning cultivation: Before harvesting the terminal curd, depending on the soil fertility conditions and the growth of the side branches retained during pruning, carry out one appropriate topdressing combined with watering 7-10 days before harvesting the main curd, so as to harvest larger side-branch curds, extend the harvest period, and increase yield. Mainly aiming for curds similar to the main curd, generally 1-2 side-branch curds can be retained per plant; for quick-freezing requirements, 4-6 side branches can be retained. According to our experimental results, an additional 200 kg can be gained per 667 sq m, and the high-quality curd rate can reach about 30%.
Broccoli must be harvested at the right time. If harvested too early, the buds have not fully developed and do not meet the standards for the finished product; if harvested too late or in high-temperature weather, the curd will loosen and may turn yellow, so close attention should be paid to water supply. If the quality deteriorates, it loses its commercial value.
According to the quality requirements abroad for our company's imported broccoli, the best is uniform and compact bud granules, no loose curd, bright green color, no "starry sky" speckling, and a height from the top of the curd to the stalk of 11-13 cm. Watering appropriately once before harvest can both increase yield and improve commercial quality.
The above is an introduction to broccoli cultivation techniques and the ratooning method. If you want to learn more, everyone is welcome to look up more information on the Agricultural Knowledge Network.