Studying the autecology of protected species can help to develop effective conservation strategies. In the case of Adonis vernalis the mean of the total number of achenes (viable and non-viable), the number of viable achenes, the number of non-viable achenes, the viable/total number of achenes ratio and the length and width of achenes were significantly different among sites. The number of flowers per individuals (genets) has a significant effect on stem height, number of viable achenes, number of non-viable achenes and on the viable/total number of achenes ratio. Unexpectedly the correlation between the number of stems and other compared values is not linear. Our results contribute to the thorough understanding of the biology of this species and can help to develop its conservation strategy.