Summary Gloriosa and Sandersonia plants were analyzed to determine their endogenous colchicine levels and the seasonal variation in alkaloid concentrations. HPlC and GCMS analysis showed that both Gloriosa superba and Sandersonia aurantiaca contained colchicine. During extraction large amounts of colchicine were photoconverted to lumicolchicine. Gloriosa and Sandersonia corm extracts contain about 0.9% colchicine, and can thus potentially be utilized as alternative sources for commercial colchicine. Colchicine levels are highest at the beginning of the growth season. As growth proceeds the levels decline, and breakdown of the chemical apparently occurs when the plant dies.