In a medium saucepan over medium heat, combine sugar and water until the sugar dissolves.
Add the lavender flowers; stir until mixture comes to a boil; reduce heat to low and simmer 5 minutes.
Remove from heat, cover, and let stand approximately 10 minutes.
Place a fine strainer over a large bowl and pour syrup mixture through (straining out the lavender flowers).
Add lemon juice and vodka to the strained syrup mixture; stir until thoroughly blended.
NOTE: The vodka (or any other type of alcohol) is the secret to a soft sorbet. Alcohol itself does not freeze and adding a little bit keeps the sorbet from doing the same. Vodka is excellent to use because it doesn't affect the taste.
Ice Cream Maker - Transfer mixture to ice cream maker, process according to manufacturer's instructions.
Freezer Method - Pour into container, cover, and place mixture in the freezer. When it is semi-solid, mash it up with a fork and refreeze again. When frozen, place in a food processor or blender and process until smooth. Cover and refreeze until serving time.
NOTE: Can be prepared 3 days in advance.
Cover and keep frozen.
Makes 8 to 10 servings.