North America Native Plant

Pringle’s Swallow-wort

Botanical name: Cynanchum pringlei

USDA symbol: CYPR11

Life cycle: perennial

Habit: vine

Native status: Native to the lower 48 states  

Synonyms: Cynanchum barbigerum (Scheele) Shinners var. breviflorum Shinners (CYBAB)  âš˜  Metastelma pringlei A. Gray (MEPR5)   

Pringle’s Swallow-Wort: A Mysterious Native Texas Treasure If you’re the type of gardener who loves discovering hidden gems in the native plant world, Pringle’s swallow-wort (Cynanchum pringlei) might just capture your imagination. This perennial herb is one of Texas’s lesser-known native plants, and honestly, that’s part of what makes it ...

Pringle’s Swallow-Wort: A Mysterious Native Texas Treasure

If you’re the type of gardener who loves discovering hidden gems in the native plant world, Pringle’s swallow-wort (Cynanchum pringlei) might just capture your imagination. This perennial herb is one of Texas’s lesser-known native plants, and honestly, that’s part of what makes it so intriguing.

What Exactly Is Pringle’s Swallow-Wort?

Pringle’s swallow-wort is a native perennial forb – basically a non-woody plant that comes back year after year. As a member of the milkweed family (though it goes by the scientific name Cynanchum pringlei), it shares some characteristics with its more famous cousins. You might also see it referenced by its botanical synonyms, including Metastelma pringlei, but don’t let the name confusion discourage you.

This plant falls into that fascinating category of forb herbs – vascular plants that stay relatively soft and herbaceous rather than developing woody stems like shrubs or trees.

Where Does It Call Home?

Here’s where things get interesting (and a bit limiting): Pringle’s swallow-wort is a Texas exclusive. This native species has chosen the Lone Star State as its sole home within the lower 48 states, making it a true regional specialty.

The Challenge of Growing the Unknown

Now, here’s where I need to be completely honest with you – Pringle’s swallow-wort is something of a mystery plant when it comes to cultivation. While we know it’s a native Texas perennial, detailed growing information is surprisingly scarce. This isn’t necessarily a bad thing; it just means you’d be venturing into relatively uncharted gardening territory.

What We Can Reasonably Assume

Based on its Texas distribution and family relationships, here’s what we can piece together:

  • Climate tolerance: Likely suited for USDA zones 8-10, given its Texas range
  • Growing conditions: Probably adapted to Texas’s variable climate conditions
  • Pollinator potential: As a member of the milkweed family, it may offer some benefits to native pollinators
  • Maintenance: Being a native perennial, it’s likely relatively low-maintenance once established

Should You Try Growing It?

If you’re a Texas gardener with a passion for native plants and don’t mind a bit of horticultural detective work, Pringle’s swallow-wort could be worth seeking out. However, there are a few things to consider:

The pros: You’d be supporting a truly local native species, and there’s something special about growing a plant that few other gardeners even know exists.

The challenges: Finding seeds or plants might be difficult, and you’ll be largely on your own when it comes to specific care instructions.

Finding and Growing Pringle’s Swallow-Wort

Your best bet for acquiring this plant would be to contact native plant societies in Texas, specialized native plant nurseries, or botanical gardens. They might have leads on seeds or know collectors who’ve worked with this species.

For growing tips, you’ll likely need to extrapolate from what works for related species and observe how your plant responds to different conditions. Start with well-draining soil and a location that mimics the natural Texas habitats where this species evolved.

The Bottom Line

Pringle’s swallow-wort represents the kind of native plant that makes regional gardening so special – it’s uniquely yours if you live in Texas. While the lack of detailed cultivation information might seem daunting, it’s also an opportunity to contribute to our understanding of this native species.

If you’re up for the challenge and can source the plant responsibly, it could become a unique addition to a native Texas landscape. Just remember, you’ll be pioneering its cultivation – and that’s pretty exciting for any dedicated native plant enthusiast.

Pringle’s Swallow-wort

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

Gentianales

Family

Asclepiadaceae Borkh. - Milkweed family

Genus

Cynanchum L. - swallow-wort

Species

Cynanchum pringlei (A. Gray) Henrickson - Pringle's swallow-wort

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