Abstract: The study is aimed to provide the experimental basis for optimum fertilizer on field production,the effect of different ratios of nitrogen (N),phosphorus (P) and potassium (K) on growth,yield,rhein and chrysophanol compounds of Hemerocallis citrina were discussed. H.citrina was used as the research object,the “3414” fertilizer test was conducted with regular fertilization of NPK (N 13.5 kg/ 667 m², P₂O₅ 40 kg/ 667 m², K₂O 15 kg/ 667 m²).The results show that the suitable level of nitrogen,phosphorus and potassium could not only promote plant growing coordination,but also improve the accumulation of rhein and chrysophanol contents.Fertilizer application could significantly increase the yield of H.citrina,and it was 457.90 kg/ 667 m² and 36.06% was the highest increasing yield in treatment of N₂P₂K₂.The contribution efficiency of nitrogen,phosphorus and potassium fertilizer application was N > P > K.The best fertilizer recommended by the single factor fertilizer effect equation was N 13.69 kg/ 667 m², P₂O₅ 31.53 kg/ 667 m², K₂O 26.40 kg/ 667 m²,which could result in H.citrina yield of 1 678.98-1 763.31 kg/ 667 m².

Key words: Hemerocallis citrina, “3414&rdquo, fertilizer test, yield, anthraquinones, optimum fertilization