A shrub, in this case, refers to a beverage made from shrub syrup. Shrub syrup is a mixture of fruit, sugar, and vinegar. This syrup is then mixed with water, sparkling water, and/or alcohol like vodka, gin, rum, or wine to make a cocktail. Shrubs first became popular in the 17th century as a way to preserve fruit, before refrigeration was available. But their pleasant, tangy flavor made them regain popularity about 8 years ago in mixology. Luckily for us, they're super easy to make at home, and what better time to start than summer when fruit is plentiful.