flower bed vs flowerbed

flower bed and flowerbed both are nouns.

Word	Noun	Adjective	Verb	Adverb
flower bed	Yes	No	No	No
flowerbed	Yes	No	No	No

As nouns, flower bed and flowerbed are synonyms defined as:

Other synonyms of flower bed include bed of flowers.

flower bed (noun)	flowerbed (noun)
a bed in which flowers are growing	a bed in which flowers are growing