By Lenn Thompson, Editor-in-Chief You don't see much viognier on Long Island and what is grown here usually ends up as a small percentage (20% or less) of local white blends, especially at Bedell Cellars, where it plays a supporting role in three different wines. But at Martha Clara Vineyards, it's bottled by itself every year, making for a unique opportunity to taste this grape. Martha Clara Vineyards 2008 Viognier ($18) bursts with white flowers on the nose with layers of honey, peach, cantaloupe and lemon balm. Medium-to-full bodied, the palate is peachy and floral with a little tropical fruit…