The lemon, Citrus × limon, is a citrus tree, a hybrid of cultivated origin. The fruit are cultivated primarily for their juice, though the pulp and rind (zest) are also used, primarily in cooking or mixing. Lemon juice is about 5% citric acid, which gives lemons a sour taste.
This is a small tree, to 6 m (20 ft) but usually smaller. The branches are thorny, and form an open crown. The leaves are elliptical-acuminate. Flowers are violet and streaked in the interior and white on the outside. On a lemon tree, flowers and ripe fruits can be found at the same time.