No, it’s not a bush that bears grapefruits. A shrub is an old-fashioned type of fruit syrup, preserved with vinegar to produce an intense fruit essence with a tart acidity—perfect for flavorful cocktail. For its variety, Liber & Co. has highlighted its home state’s most iconic citrus by creating a Texas grapefruit shrub. Starting with Rio Star grapefruits (cold-pressed to maintain zestiest flavor), the shrub is enhanced with coconut vinegar, cane sugar, and subtle notes of allspice. The result is a sweet, tart tonic that can totally electrify your next gin martini or old fashioned.