What are the fertilization timing and application rates for napa cabbage?
Napa cabbage is a vegetable native to China and has a long history of cultivation. Below we introduce the fertilization timing and application rates for napa cabbage.
1. Fertilization Timing for Napa Cabbage
The seedling stage is when napa cabbage needs the least fertilizer, but sufficient nutrients are still required to ensure its growth. After the seedling stage and once it enters the rosette stage, the demand for nutrients increases rapidly, and the level of nutrition at this time determines the final quality and yield of the napa cabbage. The fertilizer needed during the final heading stage is no less than that needed during the rosette stage, mainly potassium fertilizer with an appropriate amount of nitrogen fertilizer.
2. Fertilization Rates for Napa Cabbage
1. Base fertilizer
The fertilization rate per mu of land is about 5000 kg of high-quality decomposed farmyard manure and 40-50 kg of compound fertilizer.
2. Seedling-promoting fertilizer
The effect of the base fertilizer is relatively slow to manifest, so during the seedling stage a small amount of quick-acting nitrogen chemical fertilizer should be applied as a seedling-promoting fertilizer. At this time, the first thinning of seedlings can be carried out; after thinning, apply 5-8 kg of ammonium sulfate per mu to promote seedling growth.
3. Topdressing
When napa cabbage enters the rosette stage, its growth speed and growth amount are relatively large, and it needs a sufficient supply of fertilizer and water. High-nitrogen fertilizer and a small amount of phosphorus and potassium fertilizer should be applied as early as possible to meet the nutritional needs of napa cabbage. During this period, apply 15-20 kg of urea and 10 kg of potassium sulfate per mu, and water two days after fertilization to ensure that the fertilizer can meet the growth requirements of napa cabbage.
4. Topdressing
The heading stage is the period when the economic yield of napa cabbage is formed, with very rapid growth, and it is also the period with the greatest demand for water and fertilizer. During the heading stage, topdressing can be done in a single application or divided into 2 applications, with the first as the key one. Combined with watering, apply 15-20 kg of ammonium nitrate and 10-15 kg of potassium sulfate per mu.
Napa cabbage is a main vegetable in Northeast and North China in winter and spring. The leaves can be used for stir-frying, eating raw, salting, and pickling in sauce, and the outer leaves that fall off can still be used as feed.