When does pasture thistle bloom?

Cirsium undulatum generally blooms from June through August, producing rounded, rose-purple flower heads atop stems covered in soft gray wool.

What pollinators does pasture thistle attract?

Bees and butterflies are the main visitors to Cirsium undulatum, feeding on the nectar of its thistle-type flower heads through the summer months.

How much water does pasture thistle need once established?

Pasture thistle tolerates low water and dry soil conditions well, which suits its use in pastures, open prairies, and roadside plantings that receive little supplemental irrigation.

What growing conditions does pasture thistle prefer?

This forb does best in full sun with well-drained soil, including sandy, rocky, or gravelly ground typical of open grasslands and disturbed pasture sites.

Is Pasture Thistle HOA-friendly?

Pasture Thistle takes more care to look intentional in a front yard. Consider it for backyard or mid-zone beds rather than the street edge.

Pasture Thistle

Name: Pollinator Patch
Author: Pollinator Patch

Cirsium undulatum

Last reviewed: August 2026

Cirsium undulatum, or pasture thistle, blooms from June through August with rose-purple flower heads on woolly, silvery gray foliage. It grows well in full sun and dry, well-drained soils across open prairies and pastures.

Toxicity unknown

Pasture Thistle (Cirsium undulatum) is not listed by the ASPCA Animal Poison Control Center (opens in new tab) or the other sources we check, so we have no verdict for it either way. Absence from those lists is not a clearance. If your pet shows symptoms after eating any plant, call the ASPCA at (888) 426-4435.

Light

full sun

Water

low

Size

12"–36" H × 12"–24" W

Bloom

Jun, Jul, Aug

Native to

AZ, CA, CO, GA and 21 more states

Pollinators

bees, butterflies

Before you buy

Your city may pay you to plant this

Cities and water utilities offer rebates for replacing lawn with native and water-wise plants. We track 452 programs across 44 states, each with a link to the provider and the date we last checked it.

Find rebates in your area

Browse plants for this ecoregion

Northwestern Forested Mountains North American Deserts Central Basin and Range Southern Rockies Arizona/New Mexico Mountains Chihuahuan Deserts High Plains Southwestern Tablelands Central Great Plains Great Plains Cross Timbers Edwards Plateau Texas Blackland Prairies Central Irregular Plains Northwestern Glaciated Plains Northwestern Great Plains Northern Glaciated Plains Western Corn Belt Plains Madrean Archipelago

Pasture thistle is a native perennial with deeply lobed leaves and purple flower heads that bloom through summer. This drought-tolerant plant forms compact clumps and goes dormant in winter, leaving behind dried stems and seed heads.

Growing Pasture Thistle

Grow Pasture Thistle in full sun and low water. Mature plants reach 12 to 36 inches tall and spread 12 to 24 inches wide. Expect low maintenance to keep it looking intentional in a front yard.

In an HOA neighborhood

Pasture Thistle takes more care to keep looking intentional in a front yard. Maintenance level: low. Consider it for backyard or mid-zone beds rather than the street edge.

Works well in: backyard only.

Thistle name creates negative perception
Spiny foliage appears aggressive
Winter dormancy looks untidy

Wildlife value

The purple blooms are magnets for bees and butterflies during summer months. Seeds provide food for finches and other small birds in fall.

Common questions

When does pasture thistle bloom?: Cirsium undulatum generally blooms from June through August, producing rounded, rose-purple flower heads atop stems covered in soft gray wool.
What pollinators does pasture thistle attract?: Bees and butterflies are the main visitors to Cirsium undulatum, feeding on the nectar of its thistle-type flower heads through the summer months.
How much water does pasture thistle need once established?: Pasture thistle tolerates low water and dry soil conditions well, which suits its use in pastures, open prairies, and roadside plantings that receive little supplemental irrigation.
What growing conditions does pasture thistle prefer?: This forb does best in full sun with well-drained soil, including sandy, rocky, or gravelly ground typical of open grasslands and disturbed pasture sites.
Is Pasture Thistle HOA-friendly?: Pasture Thistle takes more care to look intentional in a front yard. Consider it for backyard or mid-zone beds rather than the street edge.

These answers were drafted with an AI model from this plant's data. Verify care details with a local expert.

Native range data from the World Checklist of Vascular Plants (Kew). Pollinator and host plant associations compiled from GBIF, iNaturalist, and published ecological literature.

If something looks wrong

Common plant problems, and what to check first

These come up on almost any plant. Each guide lists the likely causes in the order they are worth ruling out, with one thing to check before you act on any of them, and links to the source it came from.

See all plant problem guides

Ready to grow Pasture Thistle? Add it to your garden in Pollinator Patch to track it and get season-by-season care guidance.

Add this plant to your garden

iPhone app Android app

Planning a bed around it? Start a free plan with this plant

Not sure where to start? Take the 2-minute yard quiz