Of Minnesota’s native orchids, lady’s-slippers just might be the showiest. Half of North America’s twelve lady’s-slipper species are found in Minnesota. From small white lady’s-slipper to showy lady’s-slipper the flowers all have lips that look like rounded pouches for luring in pollinators. Seeds that form and are released to the wind must find a fungal partner in the ground where they land to develop into plants. Lady’s-slippers also spread from underground rhizomes so that some species form long-lived clumps. Whenever and wherever we find one of our state’s six sweet lady’s-slipper orchids, we always feel grateful.
Small white lady’s-slipper Cypripedium candidum
Only a few of Minnesota’s native orchids grow on prairies, and small white lady’s-slipper is one of them. Look for flowers blooming from mid-May to mid-June in wetter areas (usually in undisturbed prairie), one flower to a stem with up to fifty stems growing from a single root. As the pouch part of the flower drops down the flowers resemble little bird’s eggs. Small white lady’s-slipper is listed as an endangered species in Minnesota.
Ram’s head orchid Cypripedium arietinum
This small (about eight inches tall), beautiful, endangered orchid has a purplish-veined lower pouch with a white opening covered with soft, whiskery hairs. One of the flower’s purple sepals arches over the pouch like a hood. Minnesota lists it as threatened, at least in part because of habitat loss. We’ve seen it in swamp forest where the plants grow on mossy areas above the water level. The flowers also grow in drier, sandier places such as jack pine woodland. Flowers bloom in late May and very early June, and we’re always thrilled to see them.
Stemless lady’s-slipper Cypripedium acaule
You might wonder, as we did, why this lady’s-slipper is called stemless, since it clearly has what we thought at first was a green stem. But we learned that what looks like a stem rising up from the two basal leaves is actually the flower stalk while the true stem remains underground. The flower has a deep purplish-pink puckered pouch with a slit down the front, making the inside accessible only to strong pollinators such as queen bumblebees who can fight their way in. Stemless lady’s-slippers are one of only 25 plants that can grow in the most acidic bogs, but they are also found in jack pine forests, northern forests, and swamps, blooming between May and July.
Showy lady’s-slipper Cypripedium reginae
If you know only one lady’s-slipper, it is probably the showy lady’s-slipper orchid which has been Minnesota’s state flower for over a hundred years (which is also how old some populations of the plants are estimated to be). These eye-catching white-and-pink orchids can grow up to three feet tall, often in clusters, with one and sometimes two spectacular blossoms per plant in the elegantly unfolding leaves. Part of the scientific name, reginae, means queen, and even the unopened buds look regal. We were delighted in our search for all six lady’s-slippers one weekend to discover the emerging leaves of showy lady’s-slipper, which flowers from mid-June to mid-July.
Large yellow lady’s slipper Cypripedium parviflorum var. pubescens
This is Minnesota’s (and the country’s) most common orchid, one you might see glowing brightly in wet prairies, fens, or roadside ditches from May to July. Its yellow blossoms are large with round pouches and twisting yellow-green sepals that often have rust-colored stripes and speckles. Small yellow lady’s–
That said, we’ve also come across yellow lady’s-slippers that perplexed us since they seemed to fall in between large and small. Are they large yellow lady’s-slippers that haven’t reached their full height? Overachieving small yellow lady’s-slippers? Is there a medium yellow lady’s-slipper we don’t know about? Then we learned from Welby Smith’s book Native Orchids of Minnesota that when small white lady’s-slippers and yellow lady’s-slippers grow in close proximity, they can hybridize, creating yellow lady’s-slippers of varying sizes and shades.
Small yellow lady’s-slipper Cypripedium parviflorum var. makasin
True small yellow lady’s-slippers (the ones that haven’t hybridized) have twisty dark red side sepals and flowers about the size of a penny. Small yellow lady’s-slippers bloom in May and June, often as near neighbors of large yellow lady’s-slippers or small white lady’s-slippers, which is where the problem of identification comes in, since hybrids can occur in varying sizes and color. Small or large or something in-between, we love these buttery yellow blossoms.
