© E. Bēvalde

St. John's wort is a perennial, 30–100 cm tall herbaceous plant with a branched stem at the top, oblong leaves and yellow, spiky flowers. John's wort blooms from July to September. The fruit of its flower is a button.
St. John's wort is widely used in folk medicine.
The biological name of the genus ‘hypericum’ comes from the Greek words hyper – above and eikon – icon, image, picture and is related to the ancient tradition of St. On St. John the Baptist's day, i.e. June 24, when the summer solstice is also celebrated, hang flowering plants at home above an image to drive away evil and evil spirits. The English name of the plant – "St. John's Wort" or "St. John's medicinal hall". The word perforatum  in the species name refers to the small holes in St. John's wort leaves, which can be seen well by holding the plant up to the light.