Meadow Thistle

Cirsium scariosum

Native to:
Canada, United States

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Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Asteraceae
Genus:
Cirsium
Species:
Cirsium scariosum
USDA Symbol:
CISC2

Growth Characteristics

Life Cycle:
Biennial | Perennial
Growth Habit:
Forb/herb
Height:
120 cm
Light Requirements:
Full Sun
Drought Tolerance:
Medium
Bloom Months:
jun,jul,aug,sep
Bloom Colors:
white, pink, lavender

Wildlife Benefits

Bees:
★☆☆☆☆ Documented bee visitation (GBIF)
Butterflies & Moths:
★☆☆☆☆ Documented Lepidoptera association (GBIF)

Keystone Species Ranking

Pollen Specialist Bee Keystone:
★★★★☆ Native pollen specialist bee species supported by this genus (NWF)

Reported Fauna Sightings

Bees: Central bumble bee (Bombus centralis), High country bumble bee (Bombus kirbiellus), Indiscriminate cuckoo bumble bee (Bombus insularis), Two-form bumble bee (Bombus bifarius), White-shouldered bumble bee (Bombus appositus), Yellow bumble bee (Bombus fervidus), Yellow head bumble bee (Bombus flavifrons), Yellow-faced bumble bee (Bombus vosnesenskii)

Garden & Ecology Notes

Wildlife Value:
bees, butterflies, birds
Deer Resistant:
Yes
Fire Ecology:
Fire adapted — tolerates or benefits from fire
Fire Notes:
Resprouts from root crown following fire; common in post-fire meadow and montane communities.

Soil Requirements

Soil Type:
well-drained, rocky or sandy soil
pH:
6.0 - 8.0 (slightly acidic to neutral)
Drainage:
excellent drainage required
Moisture:
dry to moderate
Notes:
commonly found in open, rocky slopes and meadows

Propagation & Germination

Stratification:
Cold/moist stratification required — 30–90 days
Germination Time:
14–30 days
Notes:
Seeds germinate best after cold stratification. Light may improve germination rates.

The above propagation data sourced from Claude AI

Pre-treatment: Place seed in a warm greenhouse environment

Establishment: This plant is commonly found in the western portions of the United States and Canada, as well as the eastern-most portion of Canada.

Source: npn.rngr.net

ORGHPS Germination Guide: Sow @ 20C. If no germination in 3 months, try 4C 1-2 months, then 20C again.

Source: Ontario Rock Garden & Hardy Plant Society