Effect of sodium polyacrylate (Hydrogel) on growth and flowering of petunia

This study evaluates the separate and combined effects of sodium polyacrylate (hydrogel) and irrigation schedules on the growth and flowering of Petunia plants. Water stress is a major abiotic factor that negatively affects flower morphology and the production of high-quality blooms by disrupting plant growth, physiological processes, and metabolic functions. An experimental study was conducted using different sodium polyacrylate treatments (SP0: pure soil; SP1: 90% soil, 10% sodium polyacrylate; SP2: 70% soil, 30% sodium polyacrylate; SP3: 50% soil, 50% sodium polyacrylate) combined with varying irrigation intervals (W0: twice daily; W1: daily; W2: every other day; W3: every third day) to assess their effects on vegetative and reproductive attributes of Petunia. The results indicated that SP2 (70% soil + 30% sodium polyacrylate) significantly reduced the time to flowering and increased both the quantity and size of flowers, while SP1 (90% soil + 10% sodium polyacrylate) enhanced vegetative growth, including the number of leaves, branches, plant height, root length, and root volume. Irrigation every three days promoted earlier flowering and improved floral traits, whereas irrigation at two-day intervals favored vegetative growth. Interactive effects of sodium polyacrylate and irrigation schedules significantly influenced both morphological and floral characteristics. Based on these findings, SP2 with a three-day irrigation interval is recommended for reproductive performance, and SP1 with a two-day interval is recommended for vegetative growth of Petunia.