To prepare a composition for suppressing plant aging useful for an agrochemical-free or an agrochemical-reduced agricultural method by supporting a far infrared radiator such as tourmaline and/or a metallic oxide on a specific carrier.

This composition for suppressing plant aging composition is prepared by mixing an artificial polymer (100 pts.wt.) as a carrier with tourmaline and/or a metallic oxide (3-30 pts.wt.), providing a metallic oxide composition, then forming the resultant mixture into a stringy or sheetlike shape. Polyvinyl chloride, low-density polyethylene, an ethylene-divinyl oxide copolymer, etc., are preferred as the artificial polymer. Schorl tourmaline, lithium tourmaline, etc., are preferred as the tourmaline. Li2O, Na2O, TiO2, etc., are preferably used in combination as the metallic oxide. The composition can be used to readily carry out the suppression of germination of potatoes or bulbs or retention of freshness and/or suppression of aging of natural flowers, vegetables or fruits.