Common St. Johnswort – Hypericum perforatum
Hypericum perforatum L.
Clusiaceae (St. Johnswort family)
MI Status
Non-native
Life cycle
Multistemmed, shrublike perennial.
Leaves
Opposite, narrow oval to oblong leaves have round to pointed tips and entire margins, and attach directly to the stem. Leaves are covered with small, transparent dots when viewed against the light.
Stems
Erect with numerous branches and up to 3 feet tall. Herbaceous stems are often reddish in color and become woody at the base with maturity.
Flowers and fruit
Bright yellow to orange-yellow flowers with five petals are approximately 0.75 inch wide, often with several black dots along the petal margins. Fruit are capsules with three cells containing numerous dark brown to black, cylinder-shaped seeds.
Reproduction
Seeds and short runners.






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