St John's plant

The St John's wort (hypericum perforatum) in the garden is currently in full flower.  The plant's name comes from the fact that it flowers around St. John's day on 24 June. 
Wort is an archaic term for any plant, herb, or vegetable, used for food or as a medicine and comes from the old English wyrt, meaning root. It was administered as a remedy by the Roman military doctor Proscurides as early as the 1st century AD, and was mainly used for magic potions during the Middle Ages. 
These days there is some evidence to suggest that St. John’s wort is a viable treatment for mild to moderate major depression.