North America Native Plant

Bigelow’s Tansyaster

Botanical name: Machaeranthera bigelovii var. commixta

USDA symbol: MABIC

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Machaeranthera canescens (Pursh) A. Gray var. commixta (Greene) S.L. Welsh (MACAC4)  âš˜  Machaeranthera commixta Greene (MACO2)   

Bigelow’s Tansyaster: A Hidden Gem for Your Native Garden If you’re looking to add some late-season color to your garden while supporting local wildlife, meet Bigelow’s tansyaster (Machaeranthera bigelovii var. commixta). This charming native perennial might not be a household name, but it’s definitely worth getting to know – especially ...

Rare plant alert!

Region: Conservation status by state

Status: S4S5T3?: Status is uncertain but is somewhere between the following rankings: Inexact rank: ⚘ Subspecies or variety is vulnerable: Either very rare and local throughout its range, found only in a restricted range (even if abundant at some locations), or factors are making it vulnerable to extinction. Typically 21 to 100 occurrences or between 3,000 and 10,000 individuals. ⚘ Apparently Secure: Uncommon but not rare, and usually widespread. Possibly cause for longterm concern. Typically more than 100 occurrences in the state or more than 10,000 individuals ⚘ Secure: At very low or no risk of extinction in the jurisdiction due to a very extensive range, abundant populations or occurrences, with little to no concern from declines or threats. ⚘

Bigelow’s Tansyaster: A Hidden Gem for Your Native Garden

If you’re looking to add some late-season color to your garden while supporting local wildlife, meet Bigelow’s tansyaster (Machaeranthera bigelovii var. commixta). This charming native perennial might not be a household name, but it’s definitely worth getting to know – especially if you live in the Colorado Plateau region and want to create a garden that truly belongs in your landscape.

What Is Bigelow’s Tansyaster?

Bigelow’s tansyaster is a native perennial forb that produces delightful daisy-like flowers in shades of purple to lavender with bright yellow centers. As a member of the sunflower family, it shares that classic, cheerful flower form we all love, but with its own unique mountain west character.

This plant is a true native of the American West, naturally occurring in Colorado and Utah. It’s perfectly adapted to the challenging conditions of the Colorado Plateau, making it an excellent choice for gardeners in these regions who want to work with nature rather than against it.

Why You’ll Love This Native Beauty

There are several compelling reasons to consider adding Bigelow’s tansyaster to your garden:

  • Late-season blooms: When many flowers are calling it quits for the year, this tansyaster is just getting started, providing crucial nectar sources for pollinators preparing for winter
  • Drought tolerance: Once established, it thrives with minimal water – perfect for xeriscaping and water-wise gardens
  • Pollinator magnet: Bees, butterflies, and other native pollinators absolutely love the flowers
  • Low maintenance: This isn’t a fussy plant that demands constant attention
  • Regional authenticity: It truly belongs in Colorado and Utah landscapes

A Word About Rarity

Before we dive into growing tips, it’s important to note that Bigelow’s tansyaster has a somewhat unclear conservation status. While it’s not critically endangered, it’s not exactly common either. If you decide to grow this plant, please source it responsibly from reputable native plant nurseries rather than collecting from wild populations. This helps ensure wild plants remain undisturbed while you enjoy this beauty in your garden.

Perfect Garden Settings

Bigelow’s tansyaster shines in several types of garden settings:

  • Native plant gardens: An obvious choice for regional native landscaping
  • Xeriscaping: Excellent for water-wise landscapes
  • Rock gardens: Thrives in well-draining, rocky conditions
  • Naturalized meadows: Perfect for creating that wild look
  • Pollinator gardens: A valuable late-season nectar source

Growing Conditions and Care

The good news is that Bigelow’s tansyaster isn’t particularly demanding. Here’s what it needs to thrive:

Sunlight and Soil

This plant loves full sun and well-draining soil. It’s adapted to the often-challenging soils of its native range, so it doesn’t need rich, amended earth to be happy. In fact, overly fertile soil might make it too lush and prone to flopping over.

Watering

Once established, Bigelow’s tansyaster is quite drought tolerant. Water it regularly the first year to help it get established, then you can back off significantly. Too much water, especially in heavy soils, can actually harm the plant.

Climate Considerations

This variety is hardy in USDA zones 4-8, making it suitable for a range of mountain and high desert climates. It’s well-adapted to temperature swings and challenging weather conditions.

Planting and Maintenance Tips

Getting started with Bigelow’s tansyaster is refreshingly straightforward:

  • Planting time: Spring or early fall work best
  • Spacing: Give plants room to spread naturally
  • Mulching: A light gravel mulch works better than organic mulch
  • Pruning: Cut back spent flower stems in late fall or leave them for winter interest and seed for wildlife
  • Fertilizing: Generally unnecessary and often counterproductive

The Bottom Line

Bigelow’s tansyaster might not be the flashiest plant in the garden center, but it offers something special: a genuine connection to the landscapes of Colorado and Utah, reliable late-season beauty, and valuable wildlife habitat. For gardeners in its native range, it’s a wonderful way to create a landscape that feels authentic and supports local ecosystems.

Just remember to source your plants responsibly, and you’ll have a beautiful, low-maintenance addition to your garden that truly belongs in your corner of the world.

Bigelow’s Tansyaster

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Asteridae

Order

Asterales

Family

Asteraceae Bercht. & J. Presl - Aster family

Genus

Machaeranthera Nees - tansyaster

Species

Machaeranthera bigelovii (A. Gray) Greene - Bigelow's tansyaster

Plant data source: USDA, NRCS 2025. The PLANTS Database. https://plants.usda.gov,. 2/25/2025. National Plant Data Team, Greensboro, NC USA