Lemon balm is grown all over the world. The plant grows up to 2 feet high, sometimes higher if not maintained. In the spring and summer, clusters of small, light yellow flowers grow where the leaves meet the stem. The leaves are very deeply wrinkled and range from dark green to yellowish green in color, depending on the soil and climate. If you rub the leaves, your fingers will smell tart and sweet, like lemons. The leaves are similar in shape to mint leaves, and come from the same plant family. Hardiness Zone: 4-9. Full to part sun.