Epidendrum radicans

A vigorous terrestrial orchid with bright orange and yellow flowers, Epidendrum radicans is grown as an ornamental and for cut flowers.

Epidendrum radicans flowers
Epidendrum radicans (Image: Vaishak Kallore, Creative Commons Attribution 3.0 Unported license)

Species information

  • Scientific name: Epidendrum radicans Pav. ex Lindl.
  • Common name(s): ground-rooting epidendrum, crucifix orchid, fire-star orchid, rainbow orchid, reed-stem epidendrum
  • Synonym(s): Epidendrum pratense Rchb.f., Epidendrum rhizophorum Bateman ex. Lindl.
  • Conservation status: Not assessed according to IUCN Red List criteria.
  • Habitat: Upland areas, often on roadsides or near disturbed ground.
  • Key uses: Ornamental.
  • Known hazards: None known.

Taxonomy

  • Class: Equisetopsida
  • Subclass: Magnoliidae
  • Superorder: Lilianae
  • Order: Asparagales
  • Family: Orchidaceae
  • Genus: Epidendrum

About this species

A terrestrial orchid from tropical and subtropical America, Epidendrum radicans is often seen on roadsides or in grassland, clambering over vegetation. Its spectacular bright orange and yellow flowers are appreciated by some orchid enthusiasts. However, the plant is too vigorous for most collections and would soon take up too large a space.

The flowers of E. radicans are superficially similar to those of two common plants (Asclepias curassavicia and Lantana camara) that often grow alongside it. This led some to believe that E. radicans, which does not produce nectar, had evolved as a mimic of the others, which do. However, research by Bierzychudek in 1981 did not support this hypothesis.

Geography & Distribution

Epidendrum radicans is native to southern Mexico, Costa Rica, El Salvador, Honduras, Nicaragua, Panama and Colombia.

Widely cultivated as an ornamental, E. radicans has become naturalised in some parts of Africa, Asia and Australia, predominantly on disturbed sites.

Description

Epidendrum radicans herbarium specimen

Dried specimens of Epidendrum radicans from Kew's Herbarium

Overview: Sympodial (producing each new growth from the base of the old growth) orchid with long, cane-like stems, each with a terminal inflorescence.

Stems & leaves: Stems up to 100 cm long and 1 cm in diameter. Oval, fleshy leaves set at regular intervals along the stem. Conspicuous, white, fleshy, aerial roots emerge from the leaf axils of new growth and aid entanglement with supporting vegetation.

Flowers: Clusters of 20–30 individual flowers are held at the end of a long stalk, the whole inflorescence being up to 50 cm long.

Flowers are small and bright orange with a yellow column. They have ovate sepals and petals, and the lip is three-lobed. Each lobe is fringed and usually a lighter orange than the tepals, fading to yellow at the base of the lip.

The column (fused male and female parts) and lip are fused together, forming a single structure. Flowers are pollinated by butterflies, the proboscis of which can fit into the resulting narrow tube.

Uses

Epidendrum radicans is cultivated as an ornamental (as a garden plant in tropical regions and pot-plant elsewhere) and is also grown for cut-flowers.

It is only rarely used for producing hybrids due to its vigorous nature and because its stems tend not to be self-supporting.

Millennium Seed Bank: Seed storage

The Millennium Seed Bank Partnership aims to save plant life worldwide, focusing on plants under threat and those of most use in the future. Seeds are dried, packaged and stored at a sub-zero temperature in our seed bank vault.

A collection of Epidendrum radicans seeds is held in Kew’s Millennium Seed Bank based at Wakehurst in West Sussex.

See Kew’s Seed Information Database for further information on Epidendrum radicans seeds.

Cultivation

Epidendrum radicans should be kept at a temperature of 21–28°C, with a winter minimum of 12°C. It can be grown in an open medium (such as bark chips or charcoal) or as an epiphyte, for example by attaching a cutting to cork bark.

Due to its vigorous nature it is impractical to grow E. radicans among other plants unless support is provided and stems are regularly tied-in. The growing medium should be kept moist, without allowing the plant to sit in water (which can rot stems and roots). Weak fertiliser should be applied (usually a quarter of the stated dose for general plant fertilisers).

This species at Kew

Epidendrum radicans is grown in the behind-the-scenes Tropical Nursery at Kew.

Dried and alcohol-preserved specimens of Epidendrum radicans are held in Kew’s Herbarium, where they are available to visitors from around the world, by appointment. The details of some of these specimens can be seen online in Kew’s Herbarium Catalogue.


References and credits

Bierzychudek, P. (1981). Asclepias, Lantana and Epidendrum: a floral mimicry complex? Biotropica 13: 54–58.

Hagsater, E. et al. (2005). Orchids of Mexico. Instituto Chinoin, Mexico City.

United States Department of Agriculture GRIN (2012). Epidendrum radicans. Available online here (accessed on 9 Oct 2012).

Kew Science Editor: Saul Walker & Andre Schuiteman
Copyediting: Emma Tredwell

Although every effort has been taken to ensure that the information contained in these pages is reliable and complete, notes on hazards, edibility and suchlike included here are recorded information and do not constitute recommendations. No responsibility will be taken for readers’ own actions. Full website terms and conditions.




Follow Kew

Keep up to date with events and news from Kew

Sign up to Kew News
   

This species belongs to...

Fact Box


Isoetes eludens

Isoetes eludens

Part of an ancient group of plants related to the ferns, this species eluded discovery until 2007, hence its Latin name eludens.

Find out more about this species

Plants & Fungi blogs from Kew

Mapping Coffee in Ethiopia part two

by: Paul Little, GIS team blog
08 May 2013

Kew photographer Paul Little has just returned from accompanying a field trip to the Highlands of Ethiopia to research the impact of climate change on the vital coffee crop. Read part two of his diary of the trip.

Seed collecting on Mount Kilimanjaro

by: Emma Williams, Millennium Seed Bank blog
18 Apr 2013

Kew Gardens botanist Emma Williams recounts her experiences on a recent seed collecting expedition to Mount Kilimanjaro in Tanzania.

Mapping Coffee in Ethiopia part one

by: Paul Little, GIS team blog
16 Apr 2013

Kew photographer Paul Little has just returned from accompanying a field trip to the Highlands of Ethiopia to research the impact of climate change on the vital coffee crop. Read part one of his diary of the trip.

Kew News Alert

All Kew News

See your favourite reasons to visit