North America Native Plant

Smartweed Dodder

Botanical name: Cuscuta polygonorum

USDA symbol: CUPO

Life cycle: perennial

Habit: vine

Native status: Native to Canada âš˜ Native to the lower 48 states  

Smartweed Dodder: The Native Parasitic Plant You Probably Don’t Want to Grow Meet smartweed dodder (Cuscuta polygonorum), one of nature’s most unusual native plants that you’ve likely walked past without noticing. This perennial parasitic vine creates intricate orange webs across wetlands and disturbed areas throughout much of North America, living ...

Rare plant alert!

Region: New Jersey

Status: Highlands Listed, S2: New Jersey Highlands region ⚘ 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) ⚘

Smartweed Dodder: The Native Parasitic Plant You Probably Don’t Want to Grow

Meet smartweed dodder (Cuscuta polygonorum), one of nature’s most unusual native plants that you’ve likely walked past without noticing. This perennial parasitic vine creates intricate orange webs across wetlands and disturbed areas throughout much of North America, living entirely off other plants. While fascinating from an ecological perspective, it’s definitely not your typical garden plant.

What Makes Smartweed Dodder Special

Smartweed dodder belongs to a unique group of plants that have given up photosynthesis entirely. Instead of making their own food like most plants, these thread-like vines wrap around host plants and tap directly into their nutrient systems. The result is an intricate web of thin, orange-yellow stems that can completely cover shrubs and herbaceous plants.

As a forb herb, smartweed dodder lacks any significant woody tissue and produces small clusters of tiny white flowers that can attract small pollinators. Don’t expect any showy blooms though – this plant is all about survival strategy rather than garden appeal.

Where You’ll Find This Native Plant

Smartweed dodder is native to both Canada and the United States, naturally occurring across a wide swath of eastern and central North America. You can find it growing wild in Arkansas, Ontario, Connecticut, Quebec, Delaware, District of Columbia, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Missouri, Nebraska, New Jersey, New York, North Dakota, Ohio, Oklahoma, Pennsylvania, Rhode Island, Tennessee, Texas, Virginia, and Wisconsin.

A Rare Plant Worth Protecting (But Not Planting)

Here’s where things get interesting: despite its wide distribution, smartweed dodder is actually quite rare in some areas. In New Jersey, it holds a Highlands Listed, S2 rarity status, meaning it’s imperiled in that state. This rarity makes it an important species for conservation – but not necessarily for your backyard.

Why Most Gardeners Should Skip This One

While we always champion native plants, smartweed dodder presents some unique challenges that make it unsuitable for most garden situations:

  • It’s completely parasitic and will weaken or kill host plants
  • Once established, it can quickly spread and become difficult to control
  • It offers minimal aesthetic appeal compared to other native vines
  • It requires specific host plants (mainly smartweeds) to survive
  • Seeds are extremely difficult to germinate and establish intentionally

Growing Conditions and Habitat Needs

If you’re curious about where smartweed dodder thrives naturally, it typically grows in moist to wet soils in areas where its preferred host plants (various smartweed species and other herbs) are abundant. The plant is hardy in USDA zones 3-8, reflecting its broad natural distribution across different climate zones.

The fascinating life cycle begins when seeds germinate in spring. The tiny seedling has just a few days to find a suitable host plant before its energy reserves run out – talk about living on the edge!

Better Native Alternatives for Your Garden

If you’re drawn to native vines that support wildlife, consider these alternatives that won’t parasitize your other plants:

  • Wild grape (Vitis species) – provides food for birds and covers structures beautifully
  • American groundnut (Apios americana) – offers fragrant flowers and edible tubers
  • Wild ginger (Asarum canadense) – creates attractive groundcover in shade
  • Virginia creeper (Parthenocissus quinquefolia) – stunning fall color and bird habitat

Appreciating Nature’s Complexity

While smartweed dodder might not earn a spot in your garden, it deserves our respect as a fascinating example of evolutionary adaptation. These parasitic plants play important roles in natural ecosystems and represent millions of years of specialized evolution. If you encounter it in the wild, take a moment to appreciate this unique native species – just don’t bring it home with you!

Sometimes the best way to support native plants is simply to protect their natural habitats and marvel at their incredible diversity from a respectful distance.

Smartweed Dodder

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

Solanales

Family

Cuscutaceae Dumort. - Dodder family

Genus

Cuscuta L. - dodder

Species

Cuscuta polygonorum Engelm. - smartweed dodder

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