North America Native Plant

Clamshell Orchid

Botanical name: Prosthechea cochleata var. triandra

USDA symbol: PRCOT

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Anacheilium cochleatum (L.) Hoffmanns. var. triandrum (Ames) Sauleda, Wunderlin & B.F. Hansen (ANCOT)  âš˜  Encyclia cochleata (L.) Dressler var. triandra (Ames) Dressler (ENCOT)  âš˜  Encyclia cochleata (L.) Dressler ssp. triandra (Ames) Hágsater (ENCOT2)  âš˜  Epidendrum cochleatum L. var. triandrum Ames (EPCOT)   

Growing the Enchanting Clamshell Orchid: A Native Florida Treasure If you’re looking to add a touch of exotic beauty to your South Florida garden while supporting native biodiversity, the clamshell orchid (Prosthechea cochleata var. triandra) might just be the perfect conversation starter for your collection. This remarkable native orchid brings ...

Rare plant alert!

Region: Conservation status by state

Status: S4S5T2: Status is uncertain but is somewhere between the following rankings: Subspecies or variety is 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) ⚘ 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 ⚘ 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. ⚘

Growing the Enchanting Clamshell Orchid: A Native Florida Treasure

If you’re looking to add a touch of exotic beauty to your South Florida garden while supporting native biodiversity, the clamshell orchid (Prosthechea cochleata var. triandra) might just be the perfect conversation starter for your collection. This remarkable native orchid brings a unique charm that’s hard to find in typical garden centers – and there’s a very good reason for that rarity.

What Makes the Clamshell Orchid Special?

The clamshell orchid gets its delightful common name from its distinctive flower shape that resembles a tiny clamshell. This perennial epiphytic orchid is classified as a forb, meaning it’s an herbaceous plant without woody stems. What makes it truly special is its status as a genuine Florida native, evolved specifically for the unique conditions of the Sunshine State’s tropical ecosystems.

You might also encounter this plant listed under several botanical synonyms, including Encyclia cochleata var. triandra or Epidendrum cochleatum var. triandrum – don’t let the name variations confuse you, they’re all referring to the same charming orchid.

Where Does It Call Home?

This orchid is exclusively native to Florida within the United States, where it naturally grows as an epiphyte in tropical hardwood hammocks and cypress swamps. In the wild, you’ll find it gracefully perched on tree branches, drawing moisture and nutrients from the humid air and occasional rainfall.

A Word About Conservation

Here’s where we need to have a serious conversation: the clamshell orchid has a conservation status that indicates it’s quite rare in the wild. If you’re considering adding this beauty to your collection, it’s absolutely crucial that you source it from reputable nurseries that propagate their plants responsibly rather than collecting from wild populations. Never collect orchids from natural areas – besides being potentially illegal, it threatens the survival of these precious native plants.

Is This Orchid Right for Your Garden?

The clamshell orchid isn’t your typical low-maintenance garden plant, but for the right gardener, it’s absolutely worth the effort. Here’s what you need to know:

  • Climate requirements: Only suitable for USDA hardiness zones 10-11 (essentially South Florida)
  • Growing style: Must be grown as an epiphyte – mounted on trees or in specialized orchid growing media
  • Light needs: Filtered light or dappled shade
  • Moisture: Requires high humidity and consistent moisture without waterlogging

Perfect Garden Settings

This orchid shines in:

  • Specialized orchid collections
  • Native Florida shade gardens
  • Tropical landscape designs
  • Naturalized areas under large trees
  • Conservatory or greenhouse settings

Growing Tips for Success

Successfully growing clamshell orchids requires mimicking their natural epiphytic lifestyle:

  • Mounting: Attach to cork bark, tree fern fiber, or grow in very coarse, well-draining orchid bark mix
  • Watering: Water regularly but ensure excellent drainage – soggy roots spell disaster
  • Humidity: Maintain 50-70% humidity levels
  • Air circulation: Provide good air movement to prevent fungal issues
  • Fertilizing: Use diluted orchid fertilizer monthly during growing season

The Reward for Your Efforts

When you successfully grow this native orchid, you’re not just adding beauty to your landscape – you’re participating in conservation efforts and supporting local ecosystems. While specific pollinator relationships aren’t well-documented for this variety, native orchids generally support specialized pollinator relationships that have evolved over thousands of years.

The distinctive clamshell-shaped flowers, typically displaying purple and green coloration, create an eye-catching display that’s sure to impress fellow gardening enthusiasts and contribute to Florida’s native plant heritage.

Bottom Line

The clamshell orchid is definitely a plant for the dedicated gardener who appreciates native species and doesn’t mind a bit of specialized care. If you have the right climate, the patience for orchid growing, and access to responsibly sourced plants, this rare Florida native can be a rewarding addition to your collection. Just remember – with rarity comes responsibility, so always choose nursery-propagated plants over wild-collected specimens.

Clamshell Orchid

Classification

Group

Monocot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Liliopsida - Monocotyledons

Subclass

Liliidae

Order

Orchidales

Family

Orchidaceae Juss. - Orchid family

Genus

Prosthechea Kn. & Westc. - appendage orchid

Species

Prosthechea cochleata (L.) W.E. Higgins - clamshell orchid

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