Lemon verbena: Aloysia triphylla
The Aloysia genus is a member of the vervain family (Verbenaceaea) and grows in the wild from California as far south as Chile.
In the wild it reaches a height of almost 5 m (16 ft). It is particularly popular because of its delicious, lemon fragrance that intensifies when the leaves are crushed. The leaves are much used a medicinal herb tea and in the cosmetics industry. The small, bluish-whitethat appear in mid-summer are grouped in long panicles. Lemon verbena grows best in a sunny to partially shaded position but not in the fierce midday sun. In summer it must be watered generously and fertilized regularly. In winter, it must be put in a cool, bright, well ventilated place at a temperature of 2-5° C (36-41° F). Lack of light will lead to leaf drop.
Before taking out in the spring, plants can be pruned lightly or cut back vigorously. This is the ideal time to propagate from tip cuttings, which root very easily. Lemon verbena is prone to attack by whitefly and greenfly.