The adjective earthy runs the gamut from "crunchy" to "crude." You could use earthy to describe bohemian fashion or a vulgar comedian. Just don't use it to describe our planet.
Adding one letter y to earth changes earth's status from a noun to an adjective. And what a versatile adjective it is! You could use it in a more literal way, like the "earthy smell" coming from the vegetable garden. Or, you could use it in a more figurative way — like to describe someone who wears Birkenstock sandals and grows her own bean sprouts. Earthy can also be used to describe someone who tends to be gross or vulgar, but this use of the word is somewhat euphemistic.