Milk Thistle

This striking member of the daisy family has thorny, variegated foliage and purple blooms that resemble large thistles. Remove the blooms before seeds mature to prevent the plant from self-seeding and becoming weedy. When cut, the plant produces a white, milky liquid, which is how it got its name. The plant has been used for centuries as a treatment for diseases of the liver and gallbladder. In its native range, it is an annual, but it may overwinter in zones 5-9.

Milk Thistle Overview

Genus Name Silybum marianum
Common Name Milk Thistle
Plant Type Annual, Herb
Light Part Sun, Sun
Height 3 to 8 feet
Width 2 to 3 feet
Flower Color Blue, Purple
Season Features Summer Bloom
Special Features Cut Flowers, Low Maintenance
Zones 10, 11, 3, 4, 5, 6, 7, 8, 9
Propagation Seed
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