Arizona Thistle

Cirsium arizonicum

Native to:
Mexico, United States

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Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Asteraceae
Genus:
Cirsium
Species:
Cirsium arizonicum
USDA Symbol:
CIAR3

Growth Characteristics

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

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

Hummingbirds: Anna's Hummingbird (Calypte anna), Broad-tailed Hummingbird (Selasphorus platycercus)

Garden & Ecology Notes

Wildlife Value:
bees, butterflies, hummingbirds, birds
Deer Resistant:
Yes
Fire Ecology:
Fire adapted — tolerates or benefits from fire
Fire Notes:
Resprouts from root crown following fire; benefits from periodic burns that reduce competition.

Soil Requirements

Soil Type:
rocky, well-drained, nutrient-poor soil
pH:
6.0 - 8.0 (slightly acidic to neutral)
Drainage:
excellent drainage required
Moisture:
dry to moderate
Notes:
commonly found in arid, mountainous regions

Propagation & Germination

Stratification:
Cold/moist stratification required — 30–60 days
Germination Time:
14–30 days
Notes:
Seeds germinate best with light exposure and cool temperatures after cold stratification.

The above propagation data sourced from Claude AI

Pre-treatment: None required

Source: npn.rngr.net