Lemon Balm - Melissa Officinalis
This is a bushy plant of a similar habit to mint in that it can be invasive if not contained. It features a strong lemon flavour, and the leaves are used in cooked dishes, salads and for tea. It grows to about 70cm and prefers full sun.
Sow outside in spring in drills, keeping watered if dry. Germination may be erratic. Thin out or transplant when large enough to handle. Grow in good soil, preferably in a sunny position.