Field management measures for high-quality and high-yield broccoli

Broccoli is a premium health vegetable with excellent color, aroma, and taste, and it is also a popular product on the market. However, because broccoli has relatively high requirements for growth and development conditions, and because producers are not familiar with broccoli cultivation techniques, problems such as deformed curds, leafy curds, curd rot, deteriorated quality, and low yield often occur in production due to improper selection of varieties, sowing dates, and cultivation management measures, directly affecting the harvest. The field management measures for high-yield and high-quality broccoli are summarized as follows:

I. Management during the seedling recovery stage: Management during this stage mainly involves cooling and moisture retention to promote early seedling recovery. In addition to using shade nets to build sheds for shading and cooling, water must also be sprinkled once in the morning and once in the evening. To prevent underground pests from biting off the seedlings, milo is evenly scattered on the soil surface at planting. About 7 days after planting, apply a light application of human feces and urine or a 2-3% urea water solution to promote plant growth. To prevent and reduce the occurrence of diseases, spray once with 75% chlorothalonil 600 times solution or 50% carbendazim 600 times solution about 10 days after planting.

II. Management during the rosette stage: This stage is the period of vigorous vegetative growth for broccoli, so sufficient fertilizer and water must be provided to allow the stems and leaves to grow rapidly and lay a good nutritional foundation for achieving high yield. Topdressing is required twice during this stage. The first topdressing is when the plants begin to grow rapidly (about 15 days after planting), using a small hoe to open holes between the plants and apply urea, about 15 kg per mu; the second topdressing is carried out before the plants close the rows, when the heart leaves begin to show a twisting shape (about 30 days after planting), combining weeding with opening shallow furrows between the rows, applying fertilizer, and then hilling soil, applying 20-25 kg of compound fertilizer per mu, or 25 kg of peanut bran. Where conditions permit, it is best to apply human feces and urine once every 7-10 days during this stage. In the early rosette stage, watering should be sufficient to meet the needs of rapid plant growth and development; after the plants form a rosette, watering should be appropriately controlled to promote underground root development. Side branches that appear during this stage should be removed promptly to promote the formation of the main curd.

III. Management during the curd formation stage: To promote the transformation from vegetative growth to reproductive growth and favor curd formation, nitrogen fertilizer should be appropriately controlled during this stage, with combined application of phosphorus, potassium, and trace fertilizers such as boron and molybdenum. At the beginning of curd formation (40-50 days after planting), apply a heavy fertilizer once, with 15 kg of potassium chloride and 15 kg of compound fertilizer per mu. To reduce yellowing on the curd surface and hollow flower stems and delay plant senescence, spray the leaf surface with 0.5% borax and 0.5% ammonium molybdate solution during the curd formation stage, about once every 1 week, for 2-3 consecutive applications. Throughout the curd formation stage, field soil should be kept moist, and diseased leaves and old leaves should be removed promptly, with pests and diseases controlled. For cultivation that also harvests side curds, keep 3-4 vigorous side flower branches per plant, and the remaining side flower branches should be removed.

IV. Management during the peak harvest stage: During this stage, attention should be paid not only to promptly removing diseased leaves and old leaves to facilitate ventilation and light penetration and promote nutrient accumulation in the curds, but also to controlling moisture to prevent excessive humidity, which can cause diseases and curd mold rot. In acid rain or heavy fog weather, water should be sprinkled promptly to wash away fog water and acid rain to reduce curd rot. The suitable harvest period for broccoli is relatively short. If harvested too late, the curds become loose, the flower buds turn yellow, and quality declines; but if harvested too early, the curds are small and yield is low. Generally, the suitable harvest time is when the flower bud grains feel somewhat loose to the touch or the flower bud grains at the edge of the curd are slightly loose, and the curd surface is tight and smooth without bumps. Broccoli harvesting should preferably be done in the early morning or evening on a sunny day. When harvesting, cut the curd together with about 10 cm of tender flower stem, place it in a shaded and cool place, and package it for market as soon as possible. If it cannot be marketed in time, it must be quickly stored at low temperature. For cultivation that also harvests side curds, topdressing should also be applied once after the main curd is harvested, with about 15 kg of compound fertilizer per mu, and the side curds should be harvested when they grow to about 5 cm in diameter.