Lime is a tropical and subtropical citrus fruit tree that flowers in the late spring and produces ripe fruit in the winter. Limes are amongst the most cold sensitive of citrus fruits, which limits the regions in which they can be found and grown successfully. Lime trees have visual similarities with other citrus fruit trees, but can usually be identified by growing climate, size, foliage and young fruit development.
Look for lime trees growing in climates where temperatures never drop below 35 degrees Fahrenheit, that are generally warm and/or humid and that are at elevations below 4,000 feet.
Look for mature lime trees or shrubs that are between 6 and 13 feet in height, with thin outward spreading branches with thorns or spines along the branches. The leaves will be shaped like an elongated ellipse, with a rounded stem end and a more pointed leaf tip. The leaves will have slightly serrated edges and be a deep green color with a matte or satin, but never glossy, finish.
Identify lime tree flowers in the late spring or early summer by their creamy white color that is tinged with lavender and lightly fragrant scent, if any at all. The flowers will be less than 2 inches in diameter when fully open, with four to six long capsule-shaped petals. In the middle of the petals will be pale gold anthers carrying pollen grains.
Recognize lime tree fruits by small clusters of deep green fruit held at the tips of small thin branches in the late summer, fall and winter. When immature, the limes will have a shiny finish to the skin and when mature, a more satin or matte look and feel. Mature fruits in late fall and winter will range from 1 to 2-1/2 inches in diameter and will begin to lighten in color, acquiring a yellow blush or turning completely yellow.