The Collaborative International Dictionary
Serotinous
Serotinous \Se*rot"i*nous\, a. [L. serotinus, fr. serus late.] (Biol.) Appearing or blossoming later in the season than is customary with allied species.
Wiktionary
serotinous
a. 1 (context of conifer cones English) Requiring the heat of a wildfire to open, in order to disperse its seed. 2 Appearing or blossoming later in the season than is customary with allied species.