It is Wales's most popular spring flower and worn with pride on St David's Day. But experts from the National Museum of Wales fear the daffodil could become out of season for the national day following the results of a major school-led study plotting climate change in Wales.
Key stage 2 pupils have been planting daffodil bulbs for the past two years as part of the Spring Bulbs for Schools experiment. A recent breakdown of this year's results reveals that the average daff bloomed on March 6 13 days earlier than in 2006.
A rise in temperature and heavier rainfall is being blamed. Now experts want more schools, especially in cities where there has been low take-up, to get involved.
Danielle Cowell, education officer for SCAN education for sustainable development at the National Museum said: "This is becoming a really good indication of climate change trends in Wales."
Pupils are asked to plant daffodil bulbs and record factors influencing growth, such as shade, temperature, sunshine and rainfall. They then post their results on a website.
Records for this year show that the average monthly temperature recorded was 6.4 centigrade two degrees higher than in 2006. Rainfall was also heavier. The fastest-growing daffs were in the warmer seaside towns of West Wales, with the first reported flowering at Burton VC primary school in Milford Haven, Pembrokeshire. Slowest to flower were in the colder Valley areas.