Silybum marianum
milk thistle
A robust biennial forming a rosette of large, spiny dark green leaves with prominent white veins, and with purple flower-heads with spiny bracts, in the second year
Other common names
blessed Mary's thistleblessed thistle
see moreholy thistle
lady's thistle
leaves of Mary
Mary's thistle
Our Lady's milk thistle
Our Lady's thistle
St Mary's thistle
lady's milk
Synonyms
Carduus marianus
Buy this plant
Size
Ultimate height
1–1.5 metresTime to ultimate height
1–2 yearsUltimate spread
0.5–1 metresGrowing conditions
Moisture
Well–drainedpH
Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green White | |||
|---|---|---|---|---|
| Summer | Purple | Green White | ||
| Autumn | Green White | |||
| Winter |
Position
- Full sun
Aspect
South–facing or West–facing
Exposure
Exposed or Sheltered Hardiness
H4Botanical details
- Family
- Asteraceae
- Native to GB / Ireland
- Yes
- Foliage
- Deciduous
- Habit
- Columnar upright
- Genus
Silybum are large annuals and biennials, with basal rosettes of large, lobed leaves and thistle-like purple flower-heads with spiny bracts in summer
- Name status
Correct
- Plant range
- Mediterranean, SW Europe to Afghanistan
How to grow
Cultivation
Grow in poor to medium fertile, well-drained, neutral to slightly alkaline soil in full sun. Protect from excess winter wet
Propagation
Propagate by seed sown in late spring or early summer
Suggested planting locations and garden types
- City and courtyard gardens
- Mediterranean climate plants
- Architectural
- Cottage and informal garden
- Flower borders and beds
Pruning
No regular pruning required, but flower stems may be removed to keep foliage effect
Pests
Generally pest-free
Diseases
Generally disease-free
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