Epipactis gigantea “Stream Orchid”

Growing orchids outdoors in Reno, Nevada Part 1:

Epipactis gigantea “Stream Orchid”

By Gina Iwahashi – March 31, 2018

Ever wish you could grow orchids in your back yard?  Do you dream of groves of dendrobiums in place of iris or lady slippers in the shade of the trees?  With little rainfall, irregular temperatures that routinely drop to 0F (or lower) in the winter and up over 105F in the summer, hot dry wind and alkaline desert soils, growing many plants is a challenge.  In fact, you would never expect ANY orchids to grow in northern Nevada.

Doing a little research though, it appears that there are FOURTEEN native species in Nevada!  An impressive number, but many are not suitable for growing in a backyard.  Many require very specialized growing conditions, a few (such as the Corallorhiza species) require a host plant or fungus for nourishment.  Epipactis gigantea, on the other hand, is an easy to grow, hardy selection for backyards.

Epipactis gigantea has a couple of common names.  It is also known as the “Stream orchid” or “Chatterbox orchid” for its growth conditions and habits.  It is a North American native with a range throughout the West.  It grows as far south as central Mexico, north into British Colombia and east into the Rocky Mountains.  Backpackers and hikers routinely encounter these orchids in quiet marshy areas, streams and gravel beds without ever recognizing them as orchids.

Plant description:

Epipactis gigantea is a winter dormant perennial that grows between about 6 inches and 3 feet tall.  Height seems to depend on growing location.  The ones in my garden are about 8 inches tall but I have seen them a couple feet tall in the foothills of the Sierra Nevada.  Flowers are greenish yellow and red-brown, 1-1 ½ inches in diameter, and appear in the late spring and early summer.  A blooming orchid will continue to flower for several weeks as the flowers bloom in sequence up the stem.  The root system of the orchid forms a dense spreading clump of rhizomes.  A happy Epipactis gigantea will spread several inches a year.

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Epipactis gigantea

There are a couple of cultivars of Epipactis gigantea.  One of the showiest is a dark/mid red leafed form with reddish flowers called “Serpentine Night”.  They are a little more delicate than the species, but well worth the color in a garden.

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Epipactis gigantea “Serpentine Night”

Wild growing conditions:

In the wild, E. gigantea lives near the water.  Any water.  They have been found in stream banks, perennial seeps, the edges of lakes, in marshes and even at the margins of hot springs!  They are almost indifferent to water chemistry and temperature (if plants can grow in the water, it will).  They prefer marshy or marginal environments but survive being underwater occasionally.  They are also indifferent to soil type.  They have been found growing in gravel, sand and clay.  One clump I saw growing in the wild in California was situated on a gravel bar in the middle of a creek.  They prefer full sun, even in Reno.

Epipactis gigantea are extremely drought tolerant.  If the water source for the orchid dries up, it will go dormant and die to the ground immediately.  In the wild, it is not uncommon for these orchids to go dormant in mid to late summer and vanish until the following spring.

They are listed as hardy in USDA zones 5 through 10.  And, given the wild plant range, possibly down to zone 2.

Growing in Reno:

Plant Epipactis gigantea in a marshy area or in the margin or outflow for a pond.  Mine are planted in a bog with amended sandy soil.  Companion plants include Japanese iris, Cardinal flowers (Lobelia cardinalis) and sweet flag (Acorus calamus).  It is in full sun with ample water.  It is not mulched or covered in any way during the winter.  They are fertilized every spring with regular plant food that I use on the entire yard.

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Epipactis gigantea “Serpentine Night”

Another gardener in Reno grows hers in a plastic watering trough, set into the ground and filled with sandy, gravelly soil.  Overflow water from her pond, and supplemental watering keeps the gravel damp and the orchids happy.

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Showing Epipactis gigantea and Epipactis gigantea “Serpentine Night”

These orchids are hardy enough that you may be able to grow them in a sunny location with a flat bowl style pot set in a saucer full of water without additional protection.

Where to buy:

Please don’t dig up wild orchids!

Here are some good places to purchase Epipactis gigantea:

www.laspilitas.com

www.edelweissperennials.com

other native plant societies and nurseries

Please note:  Another Epipactis commonly seen is the invasive Epipactis helleborine, also called “broad-leaved helleborine” or “weedy orchid”.  It is a similar looking Epipactis to E. gigantea, but is taller with different leaves.  It is a native of Europe, northern Africa and parts of Asia.  DO NOT plant E. helleborine; it fills the same ecological niche and crowds out Epipactis gigantea!  (I am all for growing orchids from around the world, but please don’t let invasive plants loose in your yard!)

If you would like to read more Gina’s Blogs, look for her at:  Sumire Designs