North America Native Plant

Pammel’s Oniongrass

Botanical name: Melica subulata var. pammelii

USDA symbol: MESUP

Life cycle: perennial

Habit: grass

Native status: Native to the lower 48 states  

Pammel’s Oniongrass: A Rare Native Treasure for Northwestern Gardens Meet Pammel’s oniongrass (Melica subulata var. pammelii), a delicate native grass that’s as charming as it is uncommon. This perennial beauty might not be the showiest plant in your garden, but for those who appreciate the subtle elegance of native grasses, ...

Rare plant alert!

Region: Conservation status by state

Status: S5T1T2Q: Status is uncertain but is somewhere between the following rankings: Uncertain taxonomy: ⚘ Subspecies or variety is critically Imperiled: Extremely rare due to factor(s) making it especially vulnerable to extinction. Typically 5 or fewer occurrences or very few remaining individuals (<1,000) ⚘ Subspecies or variety is imperiled: Extremely rare due to factor(s) making it especially vulnerable to extinction. Typically 6 to 20 occurrences or few remaining individuals (1,000 to 3,000) ⚘ 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. ⚘

Pammel’s Oniongrass: A Rare Native Treasure for Northwestern Gardens

Meet Pammel’s oniongrass (Melica subulata var. pammelii), a delicate native grass that’s as charming as it is uncommon. This perennial beauty might not be the showiest plant in your garden, but for those who appreciate the subtle elegance of native grasses, it’s a real gem worth getting to know.

Where You’ll Find This Native Grass

Pammel’s oniongrass calls the northwestern United States home, naturally occurring in Idaho, Montana, and Wyoming. As a true native to the lower 48 states, this grass has been quietly gracing the region’s landscapes long before any of us started thinking about gardening.

A Word About Rarity

Here’s something important to know: Pammel’s oniongrass has a Global Conservation Status of S5T1T2Q, indicating it’s quite uncommon in the wild. If you’re considering adding this grass to your garden, please make sure you source it responsibly from reputable native plant nurseries that propagate their own stock rather than wild-collecting.

What Makes This Grass Special

Don’t let the name fool you – this isn’t related to onions at all! Pammel’s oniongrass is a true grass with a graceful, delicate appearance that adds texture and movement to any planting. As a perennial, it’ll come back year after year, slowly establishing itself as a reliable part of your landscape.

Perfect Spots for Pammel’s Oniongrass

This native grass shines in several garden settings:

  • Native plant gardens where you want authentic regional character
  • Prairie restoration projects
  • Low-maintenance naturalistic landscapes
  • Rock gardens with good drainage
  • Xeriscaping designs that celebrate drought-tolerant plants

Growing Conditions That Make It Happy

Like many western native grasses, Pammel’s oniongrass prefers:

  • Well-drained soils (it doesn’t like wet feet!)
  • Full sun to partial shade
  • USDA hardiness zones 3-6
  • Once established, it’s quite drought-tolerant

Planting and Care Tips

The good news is that once you get Pammel’s oniongrass established, it’s pretty low-maintenance. Here’s how to give it the best start:

  • Plant in spring or early fall when temperatures are moderate
  • Ensure excellent drainage – soggy soil is this grass’s biggest enemy
  • Water regularly the first growing season to help establish roots
  • After establishment, it should handle dry periods like a champ
  • Minimal fertilization needed – native soils are usually just fine

Wildlife and Pollinator Considerations

While Pammel’s oniongrass is wind-pollinated rather than insect-pollinated, it still provides valuable habitat structure in native plantings. It can offer cover and nesting material for small wildlife and contributes to the overall ecosystem health of native plant communities.

Should You Plant Pammel’s Oniongrass?

If you’re gardening in Idaho, Montana, or Wyoming and want to create authentic native plantings, Pammel’s oniongrass can be a wonderful addition – but only if you can source it responsibly. Its rarity means we need to be thoughtful about how we obtain and grow it.

For gardeners outside its native range or those who can’t find responsibly sourced plants, consider other native grasses from your region that offer similar aesthetic appeal and ecological benefits. Your local native plant society or extension office can suggest appropriate alternatives.

When grown with care and respect for its conservation status, Pammel’s oniongrass offers a unique connection to the authentic plant communities of the northwestern United States – a living piece of regional natural heritage right in your garden.

Pammel’s Oniongrass

Classification

Group

Monocot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Liliopsida - Monocotyledons

Subclass

Commelinidae

Order

Cyperales

Family

Poaceae Barnhart - Grass family

Genus

Melica L. - melicgrass

Species

Melica subulata (Griseb.) Scribn. - Alaska oniongrass

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