The present work deals with the fabrication of decomposable, agar-gelatin based semi-IPN superab-sorbent which was cast-off as template for the synthesis of bioactive nano-hydroxyapatite. Microwave assisted free-radical polymerization technique was used and the optimized reaction parameters were: initiator (mol/L): 0.021; time (sec): 15; microwave power (%): 100; AA (mol/L): 6.994; MBA (mol/L): 6.4 x 10(-3); solvent (ml): 12.5 and pH: 7.0. Semi-IPN could imbibe water to a large extent and maximum percentage swelling found was 4750%. The synthesized semi-IPN was used as mineralization matrix for the fabrication of rod-shaped nano-hydroxyapatite crystals which showed Ca/P ratio 1.665 similar to natural bone (1.67) with average crystallite size 50-100 nm (length) and 15-30 nm (diameter) respectively. Further soil water retention studies revealed that synthesized semi-IPN template could retain moisture for about 55 days, 40 days and 31 days in clayey, mix-soil and sandy soil, respectively and degraded upto 84% in 70 days using composting and 80% using vermi-composting method of biodegradation. Thus, synthesized device being antibacterial, biodegradable and ecofriendly could have a contribution in ever-green revolution also used as template for the morphology controlled synthesis of n-HA. (C) 2018 Elsevier B.V. All rights reserved.