Yes, HEATHERS is a Scrabble word!

Letter values in Scrabble US: H 4, E 1, A 1, T 1, H 4, E 1, R 1, S 1.

Is it a valid word?

HEATHERS is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

common Old World heath represented by many varieties; low evergreen grown widely in the northern hemisphere
interwoven yarns of mixed colors producing muted greyish shades with flecks of color

Also: scots heather, calluna vulgaris, heather mixture.