half-hardy vs flora

half-hardy is not a noun while flora is a noun.

Word	Noun	Adjective	Verb	Adverb
half-hardy	No	Yes	No	No
flora	Yes	No	No	No

half-hardy (noun)	flora (noun)
	(botany) a living organism lacking the power of locomotion
	all the plant life in a particular region or period

half-hardy (adjective)	flora (adjective)
(of plants) requiring protection from frost