Effect of water regimes and harvest times on yield and phytochemical accumulation of two ginger species

•Water stress treatment of 20-25% MAD increased rhizome, tiller, and leaf yield of Zingiber officinale.•Severely water-stressed irrigation regime (i.e., 80-85% MAD) enhanced total flavonoid content, phenolic content, and antioxidant activity for ginger species.•Selection of 20-25% MAD for crop yield and 80-85% MAD for secondary metabolites is desired for crop improvement strategies.•Harvesting time and plant parts contribute to adopting plant substitution and quality improvement of ginger species.