Common St. Johnswort – Hypericum perforatum

Common St. Johnswort

Hypericum perforatum L.
Clusiaceae (St. Johnswort family)

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.

Common St. Johnswort in a field
Common St. Johnswort in a field
Common St. Johnswort flower
Common St. Johnswort flower
Opposite leaves of Common St. Johnswort
Opposite leaves of Common St. Johnswort
Young Common St. Johnswort plants
Young Common St. Johnswort plants
Common St. Johnswort flower petal margin
Common St. Johnswort flower petal margin
Transparent dots visible on leaf
Transparent dots visible on leaf

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