In this work, semi-interpenetrating polymer network hydrogels with and without castor oil (S-2IPN, S-3IPN, S-4IPN, S-2IPNC, S-3IPNC and S-4IPNC) are synthesized using a free-radical solution polymerization in presence of acrylic acid as a pH-responsive monomer and dimethyl aminoethyl methacrylate as a thermoresponsive monomer with carboxymethyl cellulose (CMC) as a cellulose derivative, potassium persulphate and N, N'-methylene bisacrylamide. Castor oil, as a green chemical material, is incorporated with a ratio (1:2) to CMC. The semi-interpenetrating network structures are formed and justifications are done by ATR-FTIR and Raman spectroscopy to assure their chemical composition. TGA, SEM, XRD and AFM approve thermogravimetric analysis, phase morphology, crystallinity and surface topography, respectively. The results show that the addition of castor oil enhances the texture and stability of hydrogels. It is concluded that S-IPNC hydrogels show higher swelling capacity than S-IPN hydrogels at lower NaCl concentration and pH range (5-7), due to increasing the osmotic pressure.Therefore, castor oil could be used as a green material in interpenetrating network hydrogels for water-saving applications.According to the principle of sustainable growth, environmentally biopolymer hydrogels pose a significant potential for using as water storage in the agricultural sector.