The wine contains nothing but grapes, but it has a lavender flavor because the vineyards are surrounded by gorgeous rippling fields of lavender! The oils and aroma molecules from those plants get carried on the wind, land on the grape skins, and end up fermenting with them.
CHEMISTRY IS WHY WINE IS SO FUN! (but actually geography, geology, botany, history, anthropology, and religion are also why wine is so fun.)

