When Do Limes Ripen?

Limes are an important flavoring agent for many foods and drinks, but their susceptibility to cold weather means that most people can't grow them as a garden plant. Limes grow only in the very hottest parts of the United States or indoors in protected areas with plenty of sun. These citrus trees can bear fruit all year; but in most lime-producing areas, the biggest harvest occurs mid-to-late summer.

Gardeners grow three main species of lime: Citrus latifolia, the Tahiti, page or Persian lime; Citrus hystrix, the kaffir, makrut or Thai lime; and Citrus aurauntifolia, the Key, West Indian, Mexican or bartender's lime. Tahiti limes, which are large, green and relatively sweet, are the most common type in North America. Other lime species grown around the world include Citrus glauca, Citrus Australis and Citrus australasica, the Australian limes, and the limequat, a cross between Key limes and kumquats.

Tahiti limes are usually harvested green, though the ripe fruit is actually yellow. According to the University of Florida, these limes are ready for harvest once the fruit is dark to medium green and about 1 3/4 inches in diameter. Harvesting fruit before it reaches this size may result in sour, dry limes. Late harvesting of yellow limes often results in slightly bitter fruit. While Tahiti limes produce year-round, their largest crop comes in June through August in most locations.

The Kaffir lime tree is often used for its leaves, but it also produces a bumpy green fruit suitable for cooking and personal care products. According to the University of California-Riverside, Kaffir limes reach full maturity in late winter to early spring, when the rind turns yellow. Pick Kaffir limes before this time to prevent bitterness. Kaffir lime fruits are often quite seedy and have an astringent flavor. Their rind is a common ingredient in Thai and Laotian curries.

Like Tahitian limes, Key limes can produce fruit year-round in warm climates. However, their production is usually split into two main seasons: May through June and November through December. Picking Key limes can be difficult, due to the large number of thorns this tree produces. Harvest your Key limes when the peel color has turned dark to light green and has a smooth, slightly soft peel. Fully ripe yellow Key limes may be gathered from the ground but are best processed for their juice.