(1) **Selection of High-Quality Varieties**: The seeds used must comply with the standards set by GB8079-1987, and genetically modified varieties are strictly prohibited. Recommended high-quality carrot varieties include Beijing Whip Stalk Red, Candle Holder, Yantai 5 Inch, Xi'an Red, Nanjing Red, Five Inch Ginseng, and Kuroda 5 Inch. Before sowing, the seeds are treated to remove their bristles, which helps in better germination. After disinfection, a larger seeding rate is applied to ensure strong seedling establishment and reduce competition among plants.
(2) **Soil Preparation and Timely Sowing**: Prior to planting, 3500–75000 kg of well-decomposed organic manure per hectare should be applied, along with 1500 kg of wood ash and 225–300 kg of compound fertilizer. The soil should be deeply plowed and thoroughly mixed with the fertilizer to prevent root damage and ensure even nutrient distribution. Field leveling is essential before sowing. Typically, 525,000 to 750,000 plants are planted per hectare. In soils lacking calcium, magnesium, or boron, additional compound fertilizers containing these elements should be incorporated to enhance plant growth and yield.
(3) **Top-Dressing and Nutrient Management**: Once the seedlings emerge, regular field operations such as weeding, thinning, and removal of diseased plants should be carried out. Watering should be done promptly to support healthy development. Carrots primarily depend on basal fertilizers, so top-dressing is generally not required, reducing the risk of chemical contamination. However, if the base fertilizer is insufficient, an appropriate amount of supplementary fertilizer can be applied based on the seedling condition. For example, 15,000 kg/ha of decomposed human fecal urine can be applied before ridge formation and during plant straightening. About 25–30 days before harvest, an extra-root dressing with 45 kg/ha of potassium dihydrogen phosphate and 1875 kg of water can be applied to improve quality. In boron-deficient soils, a spray of 0.1%–0.25% borax or boric acid should be applied at the seedling, rosette, and root enlargement stages. For high-nitrogen soils, 150 kg/ha of sodium chloride (NaCl) may be used to lower nitrate levels in the roots.
(4) **Harvesting and Post-Harvest Handling**: When carrots are sown in autumn, they should be harvested promptly to avoid frost damage. All tools used during harvesting must be clean, hygienic, and free from contaminants. Proper handling, transportation, and storage should follow the guidelines outlined in DB1304/049 to maintain product quality and safety. This comprehensive approach ensures that the final product meets high agricultural and food safety standards.
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