Yes, ROQUETTE is a Scrabble word!

Letter values in Scrabble US: R 1, O 1, Q 10, U 1, E 1, T 1, T 1, E 1.

Is it a valid word?

ROQUETTE is a valid word in the official Scrabble dictionary (US) and the UK Scrabble Dictionary, but not in Words with Friends (ENABLE).

erect European annual often grown as a salad crop to be harvested when young and tender

Also: garden rocket, rocket salad, eruca sativa, eruca vesicaria sativa.