Radishes are in season from May to October and Watercress from April through November. Although Granny Smith apples are available year round in any supermarket, they are in season locally through the Fall.
Rinse your radishes and remove tops. Slice in quarters and set aside. Then core your apples and cube. Then thoroughly rinse your Watercress after removing the ends. Spin or pat dry with paper towels.
Buy a bottle of the Citrus vinaigrette from Sang Lee Farms in the town of Peconic and dress your salad just before plating.