Also called vitex, chaste berry or monk’s pepper, agnus castus is a large shrub native to southern Europe. The plant produces small, fragrant white or lilac coloured flowers in the height of summer and after pollination develops dark reddish-brown-to-black fruits about the size of peppercorns. Agnus castus has been used in herbal medicine for centuries to relieve symptoms associated with female hormonal imbalances such as menstrual cramps, mood swings and water retention.