Southernwood is native to Spain and Italy and was much used as a medicinal herb in the Middle Ages and the Renaissance. It is scarcely used these days however as modern medical research has not yet been carried out to support or disprove the uses to which southernwood has been put.
It is related to others in the Artemisia genus of plants, which include wormwood (A. absinthum), sweet wormwood (A. annua), mugwort (A. vulgaris), tarragon (A. dracunculus) and a whole host of others supposedly given by Artemis to Chiron the Centaur (after whom centaury was named, for the benefit of the human race) as he was in mythology at least, the first physician.
In French it is called garderobe meaning clothes protector as it is a moth repellent. It is said that women used to take bunches of the herb to church with them along with balm, to prevent them dozing during long-winded sermons. It was also reputed to ward off contagious diseases, and was apparently put beside prisoners in the dock in bunches along with rue so that the good people at the trial would not catch jail fever. This practice continued up until the 19th century.
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Young country boys in Britain would burn the leaves and stems and use the ash in a homemade ointment made primarily with lard, and rub it into their faces in the hope of growing a beard. Perhaps that it was why it was known by a country name of Lad’s Love. It symbolized fidelity if it were presented to a loved one in a bouquet.
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The dried, powdered leaves were given to children in a teaspoon of treacle to get rid of internal worms.
Dioscorides writing in the first century AD thought that the bruised seeds heated in water and drunk stopped pains in the joints and sciatica, while boiled in wine they were an antidote to poisonous bites. He said that if the herb was burnt, venomous creatures would not go near it.
Culpeper recommended it for worms, the spleen and said “The leaves are a good ingredient in fomentations for easing pain, dispersing swellings and stopping the process of gangrenes.” He also suggested a “wasted quince” mixed with oil of southernwood was good for inflammation of the eyes.
Of course this is for information only. If you go anywhere near southernwood, wear gloves, as it can cause dermatitis.