Connecticut Plants
Common St. Johnswort
Hypericum perforatum L.

Note the dark dots on the petals; such dots on the edges (but not the backs) of the petals distinguish common St Johnsworts from related species. The flowers have been used as a reddish dye. (If you rub a petal between your fingers, it will leave a dark red-purple stain.)

  • Family: St. Johnswort (Hypericaceae)
  • Habitat: roadsides, fields, waste places
  • Height: 1-2.5 feet
  • Flower size: 3/4 to 1 inch across
  • Flower color: yellow
  • Flowering time: June to September
  • Origin: Europe
Hypericum perforatum L.