Several fluorescent staining procedures to detect suberin in normal periderm of potato were assessed. Among the stains tested, treatment with the alkaloid fluorochrome berberine followed by counterstaining with crystal violet appears to be the most sensitive combination. Crystal violet increased contrast by quenching lignin fluorescence which is also present in the periderm cell walls. This technique may be useful for studying the role of suberin in disease resistance and wound healing of potato tubers and other tissues.