Cowslip or oxlip, for example (7)
(Other definitions for primula that I've seen before include "Spring flower" , "Flowering plant" , "Polyanthus" , "Plant such as cowslip" , "Primrose" .)
(Other definitions for bloomer that I've seen before include "Crusty loaf" , "that's made with flour!" , "Big mistake" , "Something from the baker" , "A slangy blunder or flower in blossom" .)