North America Native Plant

Slender Goldenbanner

Botanical name: Thermopsis gracilis var. gracilis

USDA symbol: THGRG

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Thermopsis gracilis Howell var. venosa (Eastw.) Jeps. (THGRV)  âš˜  Thermopsis macrophylla Hook. & Arn. var. venosa (Eastw.) Isely (THMAV2)  âš˜  Thermopsis montana Nutt. var. venosa (Eastw.) Jeps. (THMOV2)  âš˜  Thermopsis subglaber L.F. Hend. (THSU3)   

Slender Goldenbanner: A Bright Native Perennial for Pacific Coast Gardens If you’re looking to add a splash of sunny yellow to your native plant garden, slender goldenbanner (Thermopsis gracilis var. gracilis) might just be the perfect choice. This cheerful perennial brings the classic appeal of bright pea-like flowers while supporting ...

Rare plant alert!

Region: Conservation status by state

Status: S4T3T4: Status is uncertain but is somewhere between the following rankings: 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 ⚘ Subspecies or varieties is apparently secure: Uncommon but not rare, and usually widespread. Possibly cause for longterm concern. Typically more than 100 occurrences in the region or more than 10,000 individuals ⚘

Slender Goldenbanner: A Bright Native Perennial for Pacific Coast Gardens

If you’re looking to add a splash of sunny yellow to your native plant garden, slender goldenbanner (Thermopsis gracilis var. gracilis) might just be the perfect choice. This cheerful perennial brings the classic appeal of bright pea-like flowers while supporting local ecosystems in California and Oregon.

What Makes Slender Goldenbanner Special?

Slender goldenbanner is a true Pacific Coast native, naturally occurring in California and Oregon. As a member of the legume family, this perennial forb produces clusters of bright yellow flowers that create stunning vertical displays in late spring and early summer. The plant’s trifoliate leaves (think three leaflets, like clover) provide attractive foliage even when not in bloom.

This native gem grows as an herbaceous perennial, meaning it dies back to the ground each winter and emerges fresh each spring. Don’t let the word slender fool you – while it may have a more delicate appearance than some of its goldenbanner cousins, it’s perfectly capable of holding its own in the garden.

Why Grow Slender Goldenbanner?

There are several compelling reasons to consider adding this native beauty to your landscape:

  • Pollinator magnet: The bright yellow flowers attract native bees, butterflies, and other beneficial insects
  • Low maintenance: Once established, it’s quite drought tolerant and requires minimal care
  • Soil improvement: As a legume, it naturally fixes nitrogen in the soil, benefiting neighboring plants
  • Native authenticity: Perfect for creating authentic regional native plant communities
  • Seasonal interest: Provides bright color during the late spring bloom period

Growing Conditions and Care

Slender goldenbanner is surprisingly easy to grow if you can provide the right conditions. This plant thrives in USDA hardiness zones 6-9, making it well-suited to much of the Pacific Coast region where it naturally occurs.

Sunlight: Provide full sun to partial shade. While it can tolerate some shade, you’ll get the best flowering in sunnier locations.

Soil: Well-draining soil is essential. This plant doesn’t appreciate soggy conditions, so ensure good drainage. It’s adaptable to various soil types but prefers moderately fertile ground.

Water: Once established, slender goldenbanner is quite drought tolerant. During its first year, provide regular water to help establish a strong root system, then gradually reduce watering frequency.

Planting and Establishment Tips

Spring is the ideal time to plant slender goldenbanner. Here’s how to give your new plants the best start:

  • Choose a location with good air circulation to prevent fungal issues
  • Dig a hole twice as wide as the root ball but no deeper
  • Water deeply but infrequently during the first growing season
  • Avoid over-fertilizing – the plant’s nitrogen-fixing ability means it doesn’t need much supplemental nutrition
  • Allow the plant to go dormant naturally in winter

Garden Design and Landscape Use

Slender goldenbanner works beautifully in several garden styles and situations:

  • Native plant gardens: Essential for authentic Pacific Coast native plantings
  • Wildlife gardens: Supports pollinators and fits into food web relationships
  • Naturalized landscapes: Perfect for creating that wild meadow look
  • Mixed perennial borders: Adds vertical interest and bright spring color
  • Slope plantings: Helps with erosion control on hillsides

A Note About Conservation

While not critically endangered, slender goldenbanner has a conservation status that suggests it deserves our attention and care. By growing this plant in appropriate regions, you’re helping to maintain genetic diversity and supporting local ecosystems. Always source plants from reputable native plant nurseries to ensure you’re getting responsibly propagated specimens.

Is Slender Goldenbanner Right for Your Garden?

If you garden in California or Oregon and want to create habitat for native pollinators while adding cheerful spring color, slender goldenbanner could be an excellent choice. It’s particularly well-suited for gardeners who appreciate low-maintenance plants with ecological benefits.

Keep in mind that this plant is specifically adapted to Pacific Coast conditions. If you’re gardening outside its native range, consider looking for goldenbanner species native to your specific region instead.

With its bright flowers, ecological benefits, and relatively easy care requirements, slender goldenbanner offers a wonderful way to bring native beauty to your Pacific Coast garden while supporting the local ecosystem that depends on these indigenous plants.

Slender Goldenbanner

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Rosidae

Order

Fabales

Family

Fabaceae Lindl. - Pea family

Genus

Thermopsis R. Br. - goldenbanner

Species

Thermopsis gracilis Howell - slender goldenbanner

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