Pink Lady's Slipper

Cypripedium acaule

Pink lady's slipper, also known as the moccasin flower, is a showy native orchid locally common in pine barrens. This is a state-protected species in a few states. The epithet acaule means "stemless." While other lady's slippers have leafy stems, pink lady's slipper does not have a stem, but only a flower stalk with two large leaves at the base. At the tip of the stalk, there is a single large magenta to white-pink flower. The plant grows in well-drained acidic soils below pH 5, often at 4-4.5, and prefers at least partial shade.

Many forest plants commonly form friendly unions (mycorrhizae) with fungi, exchanging chemical substances to mutual benefit: the fungus delivers nutrition to the plant, while having access to sugars made by the plant. As an orchid, pink lady's slipper is one of those mycorrhizae-dependent plants. Mycorrhiza is especially critical for an orchid at the time of germination, as orchid seeds are minuscule and don't contain any stored energy. It may take a lady's slipper 20+ years to grow and develop from seed to a mature plant. Once established, plants live for many years if left undisturbed. Pink lady's slipper has a less than 5% transplant success rate and is thus considered off limits to pickers and diggers.

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May 14

May 30

Developing fruit. August 20