What is Epipactis?

Epipactis is a large terrestrial orchid genus found throughout Asia, the Americas, and Europe. These orchids are adapted to temperate to subtropical temperatures and prefer very wet, humid environments. Several species are cultivated as ornamentals by gardeners and a few have become invasive outside their native range, while others are considered threatened or endangered in the wild as a result of habitat destruction, harvesting, and other threats.

While many people think of orchids as epiphytic plants adapted to growing in the forest canopy, there are several terrestrial genera adapted to grow in the soil. Epipactis grows in wet soil and in some cases, these orchids actually prefer standing or running water. They can be found in woodlands, open spaces, and along streams and rivers where the conditions are conducive to healthy growth, and they are perennials, returning year after year.

The foliage of Epipactis species is lance-like in shape, with the leaves at the base of the plant being larger than the leaves on the top. The plants put out racemes of white, greenish, yellow, or purple flowers. The flowers and foliage die back in dry and cool weather, with the plant returning in the spring with fresh foliage and blooms. Epipactis puts out rhizomes underground to allow itself to spread, and these can be used to divide growing plants for the purpose of propagating more orchids.

These plants have a symbiotic relationship with beneficial fungi that colonize their rhizomes. In some cases, Epipactis species without chlorophyll have been identified, with the orchids using the fungi for energy. These unusual white orchids are highly visually distinctive and they are unusual. With an estimated 70 species in this genus, it is also possible that additional species are waiting to be discovered. Like many woodland plants, Epipactis can be highly variable in nature and in isolated regions, plants that have not yet been identified may be present.

People interested in growing Epipactis can obtain plants from nurseries and other gardeners who work with orchids. A moisture-retaining soil mixture will be needed to keep the plants healthy and happy, with periodic fertilization to promote healthy development of leaves and flowers. Cultivation of these orchids can be challenging, as they like their environment wet, but they can also develop mold, mildew, and rot if their environment is too wet. High humidity is also needed and temperatures need to be kept stable in a comfortable range for the plants.