Spring bloom
'spring bloom' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for iris that I've seen before include "Part of the eye, usually brown or blue" , "Lily" , "Fleur-de-lys" , "is 21[WOMAN], perhaps" , "Rainbow-goddess" .)
(Other definitions for lily that I've seen before include "Easter flower" , "Bulbous flowering plant" , "Type of flower" , "Plant with showy pendulous flowers" , "Bulbous plant with trumpet-shaped flowers" .)