While many orchids grow in hot, humid climates, the Showy Lady's Slipper (Cypripedium reginae) is cold hardy in USDA Zones 2 through 5 and the cooler parts of Zone 6. Native to the Northeast and Midwest of North America, it became the state flower of Minnesota in 1902. Locals loved to pick these orchids to adorn church alters until it became illegal to pick or dig up these plants in 1925. Now, this orchid is listed as endangered, threatened, or historical in several states.
Thriving in forested or open wetlands and moist woods, Cypripedium reginae forms large clumps in limy sites at low to moderate elevation. Inspired by reginae, which is Latin for "queen," this orchid is also commonly known as Queen Lady's Slipper.
Living up to its ideal as the queen of the garden, and indeed the showiest of lady slipper orchids, the leaves are noticeably large and ribbed. Atop each stout, hairy, leafy stalk grows one, two, or three lavishly sized and impressive-looking blooms. The sepals and petals are white, flat, and oblong, paired with a one- to two-inch pouch (or "labellum") in pink, magenta, or deep rose. The blossom is shaped much like a slipper, rounded and framed by large oval petals.
The tallest native northern orchid, it usually grows one to two feet tall while some stems grow up to 35 inches in length with three to five leaves per stem. These perennials bloom between May and August depending on the location. Individual flowers last between seven and 14 days.
It is attractive to pollinators, but it is possible that small European skipper butterflies can get trapped in the flower pouches, and this may deter bees from their usual pollinating activities.
|Botanical Name||Cypripedium reginae|
|Common Name||Showy Lady Slipper, Queen's Lady's Slipper|
|Mature Size||1 to 2 ft. tall|
|Sun Exposure||Dappled Sun/Part Shade|
|Soil Type||Moist, fertile, leafy, humus-rich soil|
|Soil pH||Acid to neutral|
|Bloom Time||Between May and August depending on location|
|Flower Color||White flower with pink-magenta pouch|
|Hardiness Zones||2-5 and cooler parts of 6, USDA|
|Native Area||Eastern North America|
|Toxicity||Hairs on leaves can be mildly toxic to humans|
Showy Lady's Slipper Orchid Care
While Showy Lady's Slipper is rare in the wild and quite challenging to grow, it is possible to cultivate this cool climate orchid in the garden with the proper care and conditions.
When planting in a shadier yard or a rock garden, dig a hole twice as big (or more) as the root ball of the Showy Lady’s Slipper orchid. Work the mix into the soil that was removed from the hole. Hold the plant over the hole. Let the base of the orchid be even with the ground level or just below it. Fill with potting mixture. Pack firmly. Only work in enough of the potting mix to support the base of the orchid.
Establish Showy Lady’s Slipper orchid in dappled sunlight or partial shade. Replicate native habitat conditions like the circumneutral peatlands or sunlit openings of mossy woods found from Newfoundland to North Dakota and Manitoba, south in the Appalachians to Georgia.
Cypripedium reginae thrives in such damp deciduous forests and on rocky outcrops in rich organic soil that is likely alkaline or based in limestone. Plants can also do well in acidic to neutral pH.
As with all Cypripedium species, be sure to give this orchid well-drained soil. Provide an evenly moist, humus-rich environment and watch it become a gem of any woodland garden.
Soak the soil completely with each watering. Then let the top two inches dry out before watering again.
Feed it a fertilizer made for orchids or one with organic ingredients like fish emulsion. Apply every two weeks throughout the growing season.
Another way of feeding the Showy Lady’s Slipper orchid is to work a time-release fertilizer into the soil at the start of the growing season. Take caution not to over-fertilize, as this could damage the plant.
Propagating Showy Lady's Slipper Orchids
Don't be tempted to uproot a wild Showy Lady's Slipper. As a result of people collecting this orchid in its natural habitat result, the wild populations have rapidly declined. Because plants take 15 years to flower, they tend to reappear rather slowly after colonies have been uprooted.
Also, plants dug up in the wild are known not to survive as often as store-bought specimens, and they have been challenging to cultivate until the late 1990s when progress was made in better understanding the tiny seeds borne on the plant's forthcoming fruits.
C. reginae seeds germinate best at least two inches deep. If dividing by rhizome, do so carefully in early to mid-spring and then transplant immediately with some of the soil from the root ball. Well cared for plants may live for up to 50 years.
Planting in Containers
If planting in a container, select a pot that is just large enough to hold the growing roots for two years. Make sure the pot has drainage holes in the bottom and the sides. When watering, let the excess water drain out.
You can use a mix of 1 part perlite, 1 part charcoal, 3 parts coarse sand, and 3 parts peat. Add a little bit of water so that the soil becomes moist but not wet.
Watch for slugs and snails. Remove any excess mulch or leaves to prevent infestation. Fill a shallow pan with beer and put it in the ground nearby to lure snails and slugs away from the orchid.
The Showy Lady's Slipper may also be a host for rust, gray mold (Botrytis), and Cercospora leaf spot. Remove infected leaves when the orchid is dry, remove any other debris around the base, and, if needed, use a commercial leaf spot remedy.