According to the Missouri Botanical Garden page for 'Lucifer': "Only reliably winter hardy to areas where winter temperatures do not dip below 0 F. In USDA Zone 5 (and possibly Zone 6), it is strongly recommended that the corms be dug up in fall and stored over winter in somewhat the same manner as for gladiolus (but do not allow them to dry out completely)."
I learned the hard way that it isn't hardy here in Zone 4
I grew up in southern England where it did exactly what greene said, so I thought it would be nice to have it here but apparently it didn't agree.
