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Milk Thistle Wikimedia Commons
Asteraceae

Milk Thistle

Silybum marianum

Healing, protection, the Virgin Mary.

Family
Asteraceae
Genus
Silybum
Native to
Mediterranean, north Africa, western Asia
Bloom season
Summer
Type
Biennial
Height
60–200 cm
Sunlight
Full sun
Soil
Average, well-drained
Water
Low; drought-tolerant
Hardiness
Annual or biennial
Lifespan
Biennial

Did you know

  • Milk thistle is named for the white-veined leaves, which Christian legend says were marked when drops of the Virgin Mary's milk fell on them — hence the species name marianum.
  • Its seeds contain silymarin, one of the most powerful liver-protective compounds known, used medicinally for over 2,000 years and still widely used today.
  • The thistle was the symbol of the medieval medical schools at Salerno and Padua and is still pictured on many pharmacy and herbalist signs.
  • Despite the spiky leaves, the flowers are an important nectar source for bumblebees, honeybees, and butterflies.
  • Milk thistle has naturalized as a weed in California pastures, where it can grow over 6 feet tall and form dense thorny stands.

Color meanings

Purple

Sacred medicine

Uses

  • Medicinal
  • Cottage gardens
  • Wildlife support
  • Herb gardens