Trim garlic heads, leaving stem intact and peeling off all but one layer of papery skin. Set aside.
Combine vinegar, sugar, peppercorns, cloves, peppers, bay leaf, and lemon rind in a medium saucepan. Bring to a boil over high heat; boil 2 minutes more. Add garlic; boil 4 minutes. Remove from heat; cover, and let sit overnight in refrigerator. Garlic may be canned, placed in a sterilized jar, or stored in the refrigerator in an airtight container up to 1 month.