North America Native Plant

Flat-top Buckwheat

Botanical name: Eriogonum smithii

USDA symbol: ERSM

Life cycle: perennial

Habit: subshrub

Native status: Native to the lower 48 states  

Synonyms: Eriogonum corymbosum Benth. var. smithii (Reveal) S.L. Welsh (ERCOS2)   

Flat-Top Buckwheat: A Rare Utah Native Worth Protecting If you’re a native plant enthusiast with a passion for conservation, flat-top buckwheat (Eriogonum smithii) might just capture your heart—and your gardening conscience. This petite shrubby perennial is one of Utah’s botanical treasures, though finding it might prove more challenging than spotting ...

Rare plant alert!

Region: Conservation status by state

Status: S1: Status is uncertain but is somewhere between the following rankings: 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) ⚘

Flat-Top Buckwheat: A Rare Utah Native Worth Protecting

If you’re a native plant enthusiast with a passion for conservation, flat-top buckwheat (Eriogonum smithii) might just capture your heart—and your gardening conscience. This petite shrubby perennial is one of Utah’s botanical treasures, though finding it might prove more challenging than spotting a needle in a haystack.

What Makes Flat-Top Buckwheat Special?

Flat-top buckwheat is a native perennial shrub that typically grows as a multi-stemmed woody plant, usually staying under 13-16 feet in height (though most specimens are much smaller). True to its name, this buckwheat species produces clusters of small flowers arranged in flattened, umbrella-like formations that create an attractive flat-topped appearance.

The plant showcases the classic buckwheat aesthetic with its silvery-green foliage and clusters of small white to cream-colored flowers that bloom during the growing season. Its compact, shrubby form makes it an interesting specimen for specialized gardens.

Where Does It Call Home?

This rare beauty is endemic to Utah, making it a true local specialty. As a species native to the lower 48 states, flat-top buckwheat has adapted to the unique growing conditions found in specific Utah locations.

A Plant on the Brink: Understanding Its Rarity

Here’s the important part every gardener needs to know: Flat-top buckwheat has a Global Conservation Status of S1, meaning it’s critically imperiled. With typically 5 or fewer occurrences in the wild and very few remaining individuals (fewer than 1,000), this plant is dancing on the edge of extinction.

What does this mean for gardeners? If you’re considering adding this species to your landscape, you absolutely must source it responsibly. Never collect plants from the wild, and only purchase from reputable native plant nurseries that can verify their propagation methods and source materials.

Garden Role and Design Potential

When responsibly sourced, flat-top buckwheat can serve as:

  • A unique specimen plant in specialized native gardens
  • An accent in rock gardens and xeriscaped landscapes
  • A conversation starter for conservation-minded gardeners
  • Part of a Utah-specific native plant collection

Growing Conditions and Care

Like many Western natives, flat-top buckwheat appreciates:

  • Soil: Well-draining, alkaline soils (poor drainage is a death sentence)
  • Sun exposure: Full sun
  • Water: Drought tolerant once established; avoid overwatering
  • USDA Hardiness Zones: Approximately zones 4-8

Planting and Care Tips

Success with flat-top buckwheat depends on mimicking its native Utah habitat:

  • Ensure excellent drainage—this cannot be overstated
  • Plant in spring after the last frost
  • Water sparingly during establishment, then reduce further
  • Avoid fertilizers, which can harm native plants adapted to lean soils
  • Mulch with gravel or decomposed granite rather than organic mulch

Benefits for Pollinators and Wildlife

The small flowers of flat-top buckwheat provide nectar for native bees and other small pollinators. As part of the buckwheat family, it supports specialized native insects that have co-evolved with these plants over thousands of years.

Should You Plant Flat-Top Buckwheat?

The answer is nuanced. If you’re passionate about conservation, have the right growing conditions, and can source plants responsibly, growing flat-top buckwheat can be part of important conservation efforts. However, given its critical status, most gardeners might consider supporting conservation in other ways—such as donating to organizations working to protect Utah’s native plant habitats.

For those determined to grow this rare beauty, work only with conservation-minded nurseries, never wild-collect, and consider it a privilege to help preserve this species for future generations.

Remember: With great rarity comes great responsibility. Every plant matters when there are so few left in the wild.

Flat-top Buckwheat

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Caryophyllidae

Order

Polygonales

Family

Polygonaceae Juss. - Buckwheat family

Genus

Eriogonum Michx. - buckwheat

Species

Eriogonum smithii Reveal - flat-top buckwheat

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