Prince-of-Wales'-heath vs Prince of Wales heath

Prince-of-Wales'-heath and Prince of Wales heath both are nouns.

Word	Noun	Adjective	Verb	Adverb
Prince-of-Wales'-heath	Yes	No	No	No
Prince of Wales heath	Yes	No	No	No

As nouns, Prince-of-Wales'-heath and Prince of Wales heath are synonyms defined as:

Prince-of-Wales'-heath and Prince of Wales heath: South African shrub grown for its profusion of white flowers

Other synonyms of Prince-of-Wales'-heath include Erica perspicua.

Prince-of-Wales'-heath (noun)	Prince of Wales heath (noun)
South African shrub grown for its profusion of white flowers	South African shrub grown for its profusion of white flowers