University of Florida

Plant Identification Learning Module:
Fruits & Nuts

Key Lime (Citrus x aurantiifolia)

The key lime is a shrubby citrus tree, to 16 feet, with many thorns. The trunk rarely grows straight, with many branches that originate quite far down on the trunk. The leaves are ovate, one to three inches long, resembling orange leaves. The flowers, one inch in diameter, are yellowish white with a light purple tinge on the edges. Flowers and fruit appear throughout the year but are most abundant from May to September. The key lime is a round fruit that is yellow when ripe but usually picked green. It is smaller, seedier, has a stronger aroma, and a thinner rind than that of the Tahiti lime (Citrus latifolia). It is valued for its unique flavor compared to other limes, with the key lime usually having a more tart and bitter flavor.