Horticulture/Melissa officinalis

Lemon balm (Melissa officinalis)is a perennial herb in the mint family Lamiaceae, native to southern Europe and the Mediterranean region.

Description
It grows to 70-150 cm tall. The leaves have a lemon scent and taste. At the end of the summer, little white flowers full of nectar appear. These attract bees, hence the genus name Melissa (Greek for 'honey bee'). Its flavour comes from the terpenes citronellal, citronellol, citral, and geraniol. Lemon Balm grows in clumps and spreads vegetatively as well as by seed. In mild temperate zones, the stems of the plant die off at the start of the winter, but shoot up again in spring.

Growing conditions
This herb can be easy to cultivate in United States Department of Agriculture Plant Hardiness Zones 4 to 9. In zone 4, it needs winter mulch and a well-drained sandy soil to survive. In zone 7, it can be harvested through late autumn. It is moderately shade-tolerant, much more so than most herbs. In dry climates, it grows best in partial shade.

Uses
It is used as a flavouring in tisane and ice cream, but its most common use is to make herbal teas. It makes a particularly refreshing iced tea, especially when mixed with other herbs such as spearmint. It is also often paired with fruit dishes or candies.

Lemon balm essential oil is very popular in aromatherapy. The essential oil is commonly co-distilled with lemon oil, citronella oil, or other oils.

The crushed leaves, when rubbed on the skin, are used as a repellant for mosquitos.

Lemon Balm is also used medicinally as a herbal tea, or in extract form. It is claimed to have antibacterial, antiviral properties, and it is also used as a mild sedative or calming agent. At least one study has found it to be effective at reducing stress, although the study's authors call for further research. Its antibacterial properties have also been demonstrated scientifically, although they are markedly weaker than those from a number of other plants studied.

Propagation
It can be easily grown from stem cuttings rooted in water, or from seeds. Under ideal conditions, it will seed itself prolifically and can become a nuisance in gardens.

Harvesting
Harvest fresh, using the leaves.