Place the lemon peel (no pith!), sugar, and rose geranium in a medium bowl.
Massage aggressively with clean hands for 5-10 minutes. Until sugar and citrus begin to meld and the peels begin to release their essential oils.
Cover and place in the refrigerator for 24 hours. Stir in lemon juice, re-cover, and refrigerate for another 12 hours or so, stirring whenever you remember. Strain syrup into container, pressing on the solids to get every last drop. Chop and save the peel solids for use in baked goods like biscotti, muffins, granola, shortbread, cakes, and the like.
Makes about 1 cup.