trefle.io · Taken Jul 26, 2017 by jose (cc-by-sa)
Asteraceae
Cotton thistle
Onopordum acanthium
Also known as Woolly thistle, Silver thistle, Scotch thistle
Native Plants · Thistle · Architectural · Wildlife Garden · Drought Tolerant · Biennial · Silver Foliage · Cottage Garden · Pollinator · Wildflower
Cotton thistle is a robust, drought-tolerant biennial that thrives in full sun with minimal watering once established. Plant in well-drained soil and give it plenty of space, as it can grow 6–9 feet tall with dramatic silvery-white spiny foliage. Deadhead spent flowers if you wish to prevent self-seeding, as it can spread readily in garden beds.
Growing conditions
The details behind the basics
- Daily light
- 6 hours
- Watering
- Water deeply but infrequently; allow soil to dry between waterings · Every 10-14 days
- Maintenance
- Low
- Soil
- loam
- Soil pH
- 7–7.5
- Temperature
- -25°F to 85°F
- Cycle
- Perennial
- Propagation
- Seed, Division
Hardiness
USDA 4b-9b
Form & growth
Mature size and habit
- Mature height
- 12 in – 3 ft
- Spread
- 2 ft
- Spacing
- 36 in apart
- Growth rate
- Moderate
- Root depth
- Medium
- Flowers
- No
- Foliage
- Medium
Ecology & origin
Where it belongs and what it brings
- Native to
- Afghanistan, Alabama, Albania, Algeria, Altay, Arizona, Austria, Baltic States, Belarus, Belgium, British Columbia, Bulgaria, California, Central European Rus, Colorado, Connecticut, Corse, Czechoslovakia, Delaware, Denmark
- Attracts
- Bees, Butterflies, Birds
Sources: trefle, usda
Buy this plant
No nurseries currently list it
No nursery lists Cotton thistle right now.