Lemon trees are a common fruit tree grown in household landscapes and can also thrive in the wild. The origins of the lemon are not known, but the citrus may have been brought to North America from Europe, where it was cultivated from India for centuries, according to Treehelp.com. The lemon tree is one of the most cold-sensitive varieties in the citrus family, so they do not grow well in the wild in any state where there are even occasional freezes. Identifying lemon trees depends on the variety, as there are several, but generally they have similar foliage and fruit.
Observe the size of the tree. At full maturity, lemon trees reach from 20 to 30 feet, but the average height ranges from 10 to 20 feet. The trees grow in a rounded shape.
Look at the foliage. Lemon trees have oval-shaped leaves with fine scalloped edges, which range from 2-and-1/2 to 4-and-1/2 inches long. The leaves tend to have a dark green upper side with a lighter green underneath. All lemon trees have small branches with thorns.
See if there are flowers on the tree. When in bloom, the lemon tree has reddish pink buds and the flowers are small, white and fragrant, growing in sets of one or two.
Look for the easiest identification of the lemon tree: the fruit, which is technically a berry. Lemons grow on average from 2-and-3/4 to 4-and-3/4 inches long. They are bright yellow and shiny with small dimples covering the thick rind. They are aromatic and spotted with oil glands.