What are the cultivation techniques for broccoli side shoots?

1. Variety selection. Based on variety characteristics, early and medium-maturing varieties can be selected as the main varieties for side shoot production, such as Youxiu, Lufeng, etc.

2. Planting density. After the main head is harvested, the plant type must be appropriately spread out to favor the growth and development of side shoot heads. Therefore, varieties intended for side shoot harvest must be planted at a moderate density; planting too densely causes poor ventilation, resulting in thin and weak side shoot head stalks that easily spread open, affecting quality. Generally, a plant spacing of 55cm and row spacing of 60cm, i.e., 2100-2200 plants per mu, is suitable.

3. Fertilizer and water management. After the main head is harvested, the base fertilizer and early topdressing have been basically consumed, so side shoot fertilizer must be added when harvesting side shoots. Generally, side shoot fertilizer is applied after 60%-70% of the main heads are harvested, which both meets the needs of side shoot growth and increases the marketable rate of the main heads. Topdressing is mainly applied per plant, with 10-15kg urea and 10kg compound fertilizer per mu. After the first batch of side shoots is harvested, if the side shoots are still growing vigorously, about 10kg/mu urea can be applied again to harvest the second batch of side shoots. In this way, 4-5 batches of side shoot heads can be harvested, with a total yield of about 500kg/mu. The soil must be kept moist throughout the growing period, but water must not accumulate in the field.

4. Pest and disease control. For exported broccoli, spraying pesticides is prohibited once the heads begin to bud. In the later stages of plant growth, pests and diseases are more common, so pest and disease control must be especially emphasized when harvesting side shoots. The main diseases in the later stage of broccoli include black rot (controlled with 80% Biken at 600 times dilution), downy mildew (controlled with 50% Shiyun at 1500 times dilution), and sclerotinia rot (controlled with 50% Xiuan at 1000 times dilution). The main pests include diamondback moth (controlled with 5% Cascade at 1200 times dilution or 24% Ruitong at 2500 times dilution) and cabbage caterpillar (controlled concurrently when controlling diamondback moth).