Bright yellow flower head of a St John's wort

St John's wort

St John's wort is sometimes considered a troublesome weed but is also used as a herbal remedy. Extracts from this tough little perennial herb are prescribed as an alternative medicine for depression. Introduced to countries outside its native Europe, St John's wort has spread aggressively and is difficult to eliminate. The origin of the common name might derive from the blooms of bright yellow flowers that appear in time for St John's Day in June, or perhaps because the dark spots on the flowers represent his blood and the translucent leaf spots the tears shed over his death. Whatever the reason, this plant has been linked to John the Baptist for centuries.

Scientific name: Hypericum perforatum

Rank: Species

Common names:

  • Common St John's wort,
  • Klamath weed,
  • Tipton's weed

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The St John's wort can be found in a number of locations including: China, Europe, Russia, United Kingdom. Find out more about these places and what else lives there.


The following habitats are found across the St John's wort distribution range. Find out more about these environments, what it takes to live there and what else inhabits them.


Discover what these behaviours are and how different plants and animals use them.

Additional data source: Animal Diversity Web


  1. Life
  2. Plants
  3. Flowering plants
  4. Dicotyledons
  5. Theales
  6. Clusiaceae
  7. Hypericum
  8. St John's wort