Editor's note: Chinese cabbage is one of the most popular vegetables among consumers. In recent years, farmers have started using winter-warm plastic greenhouses to grow cabbage during the off-season after Xiafu (a traditional period in the summer), which not only ensures a year-round supply of this vegetable but also leads to faster growth and quicker economic returns. However, with changes in cultivation techniques and management practices, many farmers have encountered problems such as loose or unformed cabbages. This has raised concerns among growers, prompting them to seek solutions. Below are the answers to their questions.
Why does Chinese cabbage fail to form properly? One major reason is improper fertilization. During the hot summer months, some farmers rush the growth of cabbages by applying excessive nitrogen-based fertilizers while neglecting phosphorus and potassium. This imbalance can lead to overly lush foliage and an underdeveloped core. Additionally, inconsistent watering can cause stress to the plants, leading to loose or hollow hearts. High humidity due to frequent summer rains can also negatively impact cabbage development, making it more prone to diseases and poor head formation. Moreover, pests and diseases like soft rot, downy mildew, and aphids can further damage the crop, contributing to the issue.
To address these challenges, farmers should adopt several effective measures. First, rational fertilization is essential. Focus on applying balanced amounts of phosphorus and potassium, along with organic matter, while limiting nitrogen use. For example, during the early and mid-stages of head formation, apply 10-15 kg per acre of potassium dihydrogen phosphate or a compound fertilizer, followed by irrigation. Second, ensure consistent and adequate watering. Water the plants in the morning and evening, avoiding midday when temperatures are highest. Mulching with weeds 3-5 cm thick helps retain soil moisture and reduce evaporation. Third, implement timely pest and disease control. Regularly inspect leaves for signs of downy mildew or soft rot, and apply appropriate fungicides such as 40% phosphine aluminum at 200-300 times dilution, or 50% methomyl at 500-600 times. Spraying every 7-8 days for 2-3 cycles can help manage outbreaks effectively. Additionally, foliar sprays of high-performance organic humic acid liquid fertilizer or a mix of urea and potassium dihydrogen phosphate can promote better head formation. Finally, consider installing shade nets over greenhouses to lower temperatures and improve growing conditions for cabbages. These strategies, when combined, can significantly improve the quality and yield of Chinese cabbage.
Sweeteners
Youth Biotech CO,. Ltd. , https://www.youtherb.com