Orchids for Your Garden
April 27-28, 2019
The Northwest's Largest Orchid Event
Most people think of orchids only as houseplants or tropicals. While it is true that most orchids grow in the tropics and, therefore, can’t grow outside year-round in Oregon, the orchid family is so diverse that many orchids will grow in temperate regions. Pretty much all of these orchids are terrestrials (grow in the ground) unlike the majority of tropical orchids that are epiphytic (grow on trees). It is worth noting, though, that many terrestrial orchids have very specific soil requirements – some of which cannot be mimicked in a typical garden. This it usually a dependency on fungal components in the soil or surrounding trees. The orchids that have such requirements, such as Calypso bulbosa and the Corallorhiza orchids, are usually not available for cultivation and are oftentimes not legal to propagate. Still, a great variety of orchids are available for garden cultivation in a climate like that in Oregon (and if you’re wondering where to buy such orchids, keep in mind that there are usually a number of vendors at the Oregon Orchid Show & Sale that sell these plants). Keep in mind that many of the orchids you’d grow in your home do like to live outside in Oregon’s summer – the sun and fresh air is usually appreciated by the plant. Below is a sampling of orchids that can live year round in the Oregon garden – many of these could live in cooler conditions as well.
If you’re an Oregonian that’s interested in growing native plants in your garden and want some of these to be orchids, consider the following plants:
Goodyera oblongifolia – the “Western Rattlesnake Plantain” is not endemic to Oregon but is a true Oregon native. This orchid is grown mostly for its beautiful variegated foliage. Successful outdoor growing will be in a shade garden in humus soil.
Cypripedium montanum – probably the showiest of orchids found in Oregon, this slipper orchid is difficult to grow but worth the effort. In the wild (where collection is HIGHLY illegal), this orchid grows on well drained slopes in mottled shade. It typically receives considerable snow in the winter (it grows in the mountains) which means that winters are actually DRY periods (since the snow is not melting for months). This is difficult to replicate in the wet, Oregon garden and most successful growers keep these plants in pots that they can put in a garage or shed for the winter but if you can prevent wetness throughout the winter, this can be planted in the ground.
Platanthera dilatata – also called the “White Bog Orchid”, this orchid is pretty easy to grow but not often found in cultivation. One reason for this is that the foliage is pretty plain and the flowers are small. It likes moist soil and can tolerate part-sun to shade.
Epipactis gigantea – this beautiful orchid is relatively common in cultivation but less common in the wild. Its common name is the “Stream Orchid”. It has a beautiful bloom and usually grows in riparian areas but could live in a well-watered Oregon garden.
Piperia elegans – This un-showy orchid has two glossy leaves that stay close to the ground. The tiny flowers are as un-showy as the rest of the plant, but if you’re a true orchid-obsessive, you’ll probably want to add this to your garden. In the wild, these grow along with Cypripedium montanum (see above) so their culture might be a bit tricky.
OTHER GARDEN ORCHIDS
Bletilla – Also called the “Chinese Ground Orchid” or “Hardy Orchid”, Bletillas come in a number of species and several hybrids. These are easy to grow and usually inexpensive. The most common species is Bletilla striata, a showy, pink orchid with good foliage. This orchid can flourish in Oregon gardens and likes sun and drained soil.
Cypripedium – There are a number of Cypripedium orchids that you can grow in your garden including Cyp. acauale, Cyp. calceolus, Cyp. debile, Cyp. formosanum, Cyp. japonicum, Cyp. kentuckiense, Cyp. parviflorum and Cyp. reginae. These all are relatively challenging to grow and can be expensive to purchase, but the rewards of successful growing are great – they are very beautiful, unique slipper orchids that will be gems in your garden. Pretty much all of them want well drained, humus soil and prefer dry winters, which is difficult to do in Oregon.
Dactylorhiza – There are a number of Dactylorhiza species (and hybrids) that will thrive in your garden. Their foliage is typically low to the ground. This is in sharp contrast to their stout bloom-spikes with numerous, lavender or white flowers. This orchid likes moist soil and partial sun to full sun.
Spiranthes – Hard to find and harder to grow, Spiranthes are beautiful, bog-loving orchids. As their name suggests, the orchid’s inflorescence develops in a spiral. Since they grow in alpine bogs, some of which dry up by the fall, their seasonal requirements are nearly impossible to replicate.
Cymbidium goeringii – At the very edge of our growing zone, this orchid is not really suitable for growing in the ground but it can typically spend the entire year outside in Oregon (along with a number of other very cool growing Cymbidiums such as Cym. sinense). It doesn’t want to get very wet in the winter (it grows under snow in Japan, so it stays dry like most Cypripedums) and that can be very difficult to replicate in Oregon’s wet winters. You don’t want it to get much below 25 degrees and well-drained mix is needed. Keeping it potted will allow you to bring the plant into a shed or garage if conditions become unsuitable.
REMEMBER collection of orchids from the wild is typically illegal and irresponsible. The orchids described here can be found in cultivation. Some are harder to source than others, but you can be sure to find a good variety of these at our annual Oregon Orchid Show and Sale.