1、 Base fertilizer

Base fertilizer must be applied well when planting yam, because its growth cycle is relatively long, so there is a great demand for fertilizer. It is usually mainly organic fertilizer or rotten farm fertilizer. This kind of fertilizer can slowly and permanently release fertility, so as to provide nutrition for its whole growth period. Generally, 2000-4000 kg of farm manure should be used per mu, together with 60-80 kg of compound fertilizer. If organic fertilizer is used, it needs to be applied with about 2000 kg, 20-30 kg of urea and 40-50 kg of phosphorus and potassium fertilizer

2、 Topdressing

1. Before emergence: after yam sowing, manure needs to be applied once before emergence. The fertilizer should be fully decomposed, otherwise once fermented, it will burn the seedlings. This fertilizer can not only provide nutrients for plant growth, but also increase ground temperature and accelerate seed emergence

2. After transplanting: generally, it is necessary to apply fertilizer once after the seedlings are ready or after transplanting. The fertilizer can continue to use manure or nitrogen fertilizer. As early fertilization, it is mainly to accelerate the growth of plant stems and leaves, so it is necessary to ensure sufficient nitrogen. However, we should also control the concentration. If there is too much nitrogen fertilizer, it will grow in vain

3. Budding period: when the yam bud appears, it needs to supplement fertilizer. At this time, it has a high demand for fertilizer. It must apply enough fertilizer to make its flowers bloom. Cake fertilizer or compound fertilizer is usually selected, which can improve more comprehensive nutrients. Only 25 kg per mu is enough