Aims: This study aimed to examine heat curing effect (30-100 degrees C) on antifungal activities of lime oil and its components (limonene, p-cymene, -pinene and -pinene) at concentrations ranging from 100 to 300l ml(-1) against Aspergillus niger in microbiological medium and to optimize heat curing of lime oil for efficient mould control on sedge (Lepironia articulata). Methods and Results: Broth dilution method was employed to determine lime oil minimum inhibitory concentration, which was at 90l ml(-1) with heat curing at 70 degrees C. Limonene, a main component of lime oil, was an agent responsible for temperature dependencies of lime oil activities observed. Response surface methodology was used to construct the mathematical model describing a time period of zero mould growth on sedge as functions of heat curing temperature and lime oil concentration. Heat curing of 90l ml(-1) lime oil at 70 degrees C extended a period of zero mould growth on sedge to 18weeks under moist conditions. Conclusions: Heat curing at 70 degrees C best enhanced antifungal activity of lime oil against A.niger both in medium and on sedge. Significance and Impact of the Study: Heat curing of lime oil has potential to be used to enhance the antifungal safety of sedge products.