Reduced fertilizer with amino acids improves soil, yield, and quality of edible rose

Abstract Long‐term excessive inorganic fertilizer application disrupts soil biological processes, diminishes nutrient use efficiency, and ultimately constrains sustainable production of edible roses. A 2‐year field experiment was carried out to explore the regulatory effects of reduced inorganic fertilizer combined with amino acid fertilizer on rhizosphere soil environment, yield, and quality. The experiment followed a two‐factor design comprising inorganic fertilizer and amino acid fertilizer. Treatments consisted of five levels of inorganic fertilizer (F 500 : 500, F 700 : 700, F 900 : 900, F 1100 : 1100 and F 1300 : 1300 kg ha −1 year −1 of blended NPK fertilizer [N:P 2 O 5 :K 2 O = 20–20–20]) and two amino acid fertilizer level (M 0 : 0, M 150 : 150 kg ha −1 year −1 ). Soil nutrient availability, enzyme activities, microbial abundance, yield, and quality were systematically evaluated. Partial least squares structural equation modeling (PLS‐SEM) and entropy weight‐technique for order preference by similarity to ideal solution (TOPSIS) were integrated to evaluate fertilization performance. Compared with single inorganic fertilization, the combined practice significantly improved soil nutrients, enzyme activities, and microbial abundance, and promoted yield and quality, with respective increases of 6.88%–40.02%, 3.82%–27.37%, 3.16%–15.71%, 6.24%–31.93%, and 1.38%–20.39%. PLS‐SEM suggested that fertilization was associated with yield and quality via soil nutrient availability, enzyme activities, and microbial abundance. TOPSIS evaluation identified the treatment with 900 kg ha −1 year −1 (N:P 2 O 5 :K 2 O = 20–20–20) inorganic fertilizer combined with 150 kg ha −1 year −1 amino acid fertilizer as the optimal regime. Integrating reduced inorganic fertilizer with amino acid fertilizer can improve rhizosphere nutrient status while sustaining high yield and quality, providing theoretical and technical support for edible rose cultivation.