North America Native Plant

Cup Plant

Botanical name: Silphium perfoliatum var. connatum

USDA symbol: SIPEC2

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Silphium connatum L. (SICO11)  âš˜  Silphium perfoliatum L. ssp. connatum (L.) Cruden (SIPEC)  âš˜  Silphium scabrum Moench, non Walter (SISC5)   

Cup Plant (Silphium perfoliatum var. connatum): A Rare Native Gem for Your Garden Meet one of the Southeast’s best-kept botanical secrets: the cup plant variety Silphium perfoliatum var. connatum. While you might be familiar with the more common cup plant species, this particular variety is a special southeastern native that ...

Rare plant alert!

Region: Conservation status by state

Status: S5T3T4: 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. ⚘ 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 ⚘ Secure: At very low or no risk of extinction in the jurisdiction due to a very extensive range, abundant populations or occurrences, with little to no concern from declines or threats. ⚘

Cup Plant (Silphium perfoliatum var. connatum): A Rare Native Gem for Your Garden

Meet one of the Southeast’s best-kept botanical secrets: the cup plant variety Silphium perfoliatum var. connatum. While you might be familiar with the more common cup plant species, this particular variety is a special southeastern native that deserves a spot in conservation-minded gardens.

What Makes This Cup Plant Special?

This perennial forb (that’s garden-speak for a non-woody flowering plant) belongs to the sunflower family and shares many characteristics with its more widespread cousin. As a native plant to Maryland, North Carolina, Virginia, and West Virginia, it’s perfectly adapted to southeastern growing conditions.

You might also see this plant listed under its synonyms: Silphium connatum, Silphium perfoliatum ssp. connatum, or Silphium scabrum. Don’t let the scientific names intimidate you – they all refer to the same wonderful plant!

A Conservation Priority

Important note for responsible gardeners: This variety has a Global Conservation Status of S5T3T4, indicating it has limited distribution and may be of conservation concern. If you’re interested in growing this plant, please ensure you source it responsibly from reputable native plant nurseries or seed companies that ethically collect seeds. Never dig plants from the wild!

Why Grow Cup Plant in Your Garden?

While specific information about this variety’s characteristics is limited, cup plants in general are fantastic additions to native gardens. Here’s why you might want to consider this southeastern native:

  • Native heritage: As a true native to the lower 48 states, it supports local ecosystems
  • Perennial reliability: Once established, it returns year after year
  • Prairie garden appeal: Perfect for wildflower meadows and naturalized areas
  • Conservation value: Growing rare natives helps preserve genetic diversity

Growing Conditions and Care

Since specific growing information for this variety is limited, we recommend following general cup plant cultivation practices while monitoring your plants closely. Based on its native range in the Southeast, this variety likely prefers:

  • Full sun to partial shade locations
  • Moist to moderately dry soils
  • USDA hardiness zones 6-8 (estimated based on native range)
  • Well-draining soil with organic matter

Garden Design Ideas

This cup plant variety works beautifully in:

  • Native plant gardens focused on southeastern species
  • Prairie-style plantings and wildflower meadows
  • Rain gardens and naturalized landscapes
  • Conservation gardens supporting rare plants

Planting and Care Tips

Given this plant’s conservation status, treat it with extra care:

  • Start with seeds or plants from reputable sources only
  • Allow plants to self-seed to help maintain local populations
  • Avoid disturbing established plants unnecessarily
  • Share seeds responsibly with other conservation-minded gardeners
  • Monitor plant health and growing conditions closely

The Bottom Line

While we’d love to provide more specific details about Silphium perfoliatum var. connatum, its rarity means there’s still much to learn about this southeastern native. What we do know is that it represents an important piece of our regional botanical heritage.

If you’re a gardener who loves supporting conservation efforts and growing unique native plants, this cup plant variety might be worth seeking out – just remember to source it responsibly and treat it as the botanical treasure it is!

Have you grown this rare cup plant variety? We’d love to hear about your experiences with this special southeastern native in the comments below.

Cup Plant

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

Asterales

Family

Asteraceae Bercht. & J. Presl - Aster family

Genus

Silphium L. - rosinweed

Species

Silphium perfoliatum L. - cup plant

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