The first flowering dates of 26 Narcissus cultivars were recorded over a 27-year period on the island of Guernsey, within the English Channel. We analysed flowering trends over time and relationships with climate variables. The study revealed that earlier flowering cultivars advanced most and were more variable than later flowering Narcissus. We furthermore discovered a strong relationship between flowering and climate variables, with temperature appearing to be the main driver. Whilst the first flowering date averaged over all cultivars did show a significant advance, this was significant for only one of the individual cultivars. This is likely because temperatures from December to March had not significantly increased in Guernsey during the study period (1985 to 2011).