Place blossoms in a strainer; rinse under cold water. Combine blossoms, water, and sugar in a medium saucepan; bring to a boil. Reduce heat, and simmer 10 minutes. Strain; discard blossoms. Cover and chill hibiscus mixture.
Combine hibiscus mixture, tequila, juice, and Triple Sec. Serve over ice. Garnish with lime slices.
Hibiscus blossoms can be found at Latin grocery stores. Boiling the blossoms in a sugar-water mixture and then steeping infuses more flavor than just steeping them in warm water. This drink is especially good when made with premium-quality tequila.