Tansy-aster
Machaeranthera tanacetifolia
Last reviewed: August 2026
Tansy-aster (Machaeranthera tanacetifolia) is a drought-tolerant native wildflower blooming purple from June through September across western and central United States.
Toxicity unknown
Tansy-aster (Machaeranthera tanacetifolia) 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.
The USDA PLANTS Database (opens in new tab) does not flag Tansy-aster as toxic to livestock.
Light
full sun
Water
low
Size
12"–24" H × 12"–18" W
Bloom
Jun, Jul, Aug, Sep
Native to
AZ, CA, CO, KS and 9 more states
Pollinators
bees, butterflies
Before you buy
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Tansy-aster is a compact annual wildflower that produces masses of small, daisy-like purple flowers with yellow centers from June through September. This drought-tolerant native grows in a neat, bushy form and readily self-seeds to create natural colonies in sunny, dry locations.
Growing Tansy-aster
Grow Tansy-aster in full sun and low water. Mature plants reach 12 to 24 inches tall and spread 12 to 18 inches wide. Expect low maintenance to keep it looking intentional in a front yard.
In an HOA neighborhood
Tansy-aster 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.
- Annual nature means gaps in coverage
- Self-seeding can appear uncontrolled
- May look weedy to traditional landscaping preferences
Wildlife value
The abundant blooms attract native bees, butterflies, and other beneficial insects throughout the growing season. Seeds provide food for finches and other small birds in fall.
Common questions
- When does Tansy-aster bloom?
- Machaeranthera tanacetifolia blooms from June through September, producing purple daisy-like flowers that attract bees and butterflies.
- What pollinators visit Tansy-aster?
- Tansy-aster attracts bees and butterflies with its late summer blooms, making it valuable for pollinator gardens in arid regions.
- Where is Tansy-aster native?
- This wildflower is native to 13 states including Arizona, California, Colorado, Kansas, Montana, Nebraska, New Mexico, Nevada, Oklahoma, South Dakota, Texas, Utah, and Wyoming.
- What growing conditions does Tansy-aster need?
- Machaeranthera tanacetifolia thrives in full sun with low water requirements, making it well-suited for xeriscaping and natural prairie gardens.
- Is Tansy-aster toxic to livestock?
- The USDA PLANTS Database does not flag Tansy-aster as toxic to livestock.
- Is Tansy-aster HOA-friendly?
- Tansy-aster 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 vouchered herbarium specimen records and regional native plant society lists. Pollinator and host plant associations compiled from GBIF, iNaturalist, and published ecological literature.
Ready to grow Tansy-aster? Add it to your garden in Pollinator Patch to track it and get season-by-season care guidance.
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