North America Native Plant

Sampson’s Snakeroot

Botanical name: Orbexilum pedunculatum var. pedunculatum

USDA symbol: ORPEP2

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Hedysarum pedunculatum Mill. (HEPE4)  âš˜  Orbexilum pedunculatum (Mill.) Rydb. var. eglandulosum (Elliott) Isely (ORPEE)  âš˜  Psoralea pedunculata (Mill.) Vail (PSPE3)  âš˜  Psoralea psoralioides (Walter) Cory var. eglandulosa (Elliott) Freeman (PSPSE)   

Sampson’s Snakeroot: A Hardy Native Wildflower for Your Garden If you’re looking to add some authentic American charm to your garden while supporting local wildlife, let me introduce you to Sampson’s snakeroot (Orbexilum pedunculatum var. pedunculatum). This delightful native perennial might not have the flashiest name in the plant world, ...

Sampson’s Snakeroot: A Hardy Native Wildflower for Your Garden

If you’re looking to add some authentic American charm to your garden while supporting local wildlife, let me introduce you to Sampson’s snakeroot (Orbexilum pedunculatum var. pedunculatum). This delightful native perennial might not have the flashiest name in the plant world, but don’t let that fool you – it’s a real gem for gardeners who appreciate understated beauty and ecological value.

What Makes Sampson’s Snakeroot Special?

Sampson’s snakeroot is a true-blue American native, belonging to the pea family and bringing that characteristic legume charm to your landscape. As a perennial forb, it’s the kind of plant that keeps giving year after year without demanding much in return – exactly the type of low-maintenance friend every gardener needs.

This lovely wildflower produces clusters of purple-blue pea-like flowers that bloom from summer through fall, creating a gentle splash of color when many other native plants are winding down for the season. The flowers are arranged in terminal spikes that rise above the foliage, making them perfect landing pads for visiting pollinators.

Where Does It Call Home?

Sampson’s snakeroot has quite an impressive natural range across the eastern and central United States. You’ll find this adaptable native growing naturally in Alabama, Arkansas, Florida, Georgia, Illinois, Indiana, Kansas, Kentucky, Louisiana, Maryland, Michigan, Mississippi, Missouri, North Carolina, Ohio, Oklahoma, South Carolina, Tennessee, Texas, and Virginia.

This wide distribution tells us something important: this plant is remarkably adaptable and can handle various growing conditions across different climate zones.

Why Your Garden (and Local Wildlife) Will Love It

Here’s where Sampson’s snakeroot really shines – it’s a pollinator magnet! Those purple-blue flowers aren’t just pretty to look at; they’re specifically designed to attract native bees, butterflies, and other beneficial insects. By planting this native wildflower, you’re essentially rolling out the welcome mat for the local ecosystem.

From a design perspective, Sampson’s snakeroot works beautifully in:

  • Native plant gardens
  • Prairie restorations and wildflower meadows
  • Naturalized woodland edges
  • Pollinator gardens
  • Low-maintenance landscape areas

Growing Sampson’s Snakeroot Successfully

One of the best things about this native wildflower is how easy-going it is once you understand its preferences. Sampson’s snakeroot thrives in USDA hardiness zones 4-8, making it suitable for most temperate regions of the country.

Light Requirements: This adaptable plant does well in full sun to partial shade, though it tends to bloom more prolifically with at least 6 hours of direct sunlight daily.

Soil Needs: Well-drained soil is key – Sampson’s snakeroot doesn’t appreciate wet feet. It’s quite drought tolerant once established, making it perfect for those areas of your garden that don’t get regular irrigation.

Planting Tips: Spring is the ideal time to plant. Give your Sampson’s snakeroot some space to spread – while it’s not aggressive, it does appreciate room to develop its natural form. Water regularly during the first growing season to help establish a strong root system, then step back and let nature take its course.

Care and Maintenance

Here’s the really good news: Sampson’s snakeroot is wonderfully low-maintenance. Once established, it’s quite drought tolerant and doesn’t require fertilization – in fact, like many native plants, it often performs better in average to poor soils than in overly rich conditions.

You can deadhead spent flowers if you prefer a tidier appearance, or leave them for the seeds to provide food for birds. In late fall or early spring, you can cut back the previous year’s growth to make room for new shoots.

The Bottom Line

Sampson’s snakeroot might not be the showiest plant in your garden, but it’s definitely one of the most valuable. It offers authentic native beauty, supports local pollinators, requires minimal care once established, and brings a piece of natural American landscape to your backyard. For gardeners who appreciate plants with both ecological value and understated charm, this native wildflower is definitely worth considering.

Whether you’re creating a prairie garden, adding to a pollinator-friendly landscape, or simply want a reliable native perennial that won’t demand constant attention, Sampson’s snakeroot delivers on all fronts. Sometimes the best garden additions are the ones that quietly do their job while supporting the bigger picture of a healthy, sustainable landscape.

Sampson’s Snakeroot

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

Orbexilum Raf. - leather-root

Species

Orbexilum pedunculatum (Mill.) Rydb. - Sampson's snakeroot

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