Summary
In autumn, Chadds Ford Atlantic ladies’-tresses (Spiranthes bightensis ‘Chadds Ford‘) makes its surprising floral debut. Rising to 18” tall, the stem bears small, fragrant white flowers arranged in an intriguing spiral. The basal strap-like evergreen leaves of this delicate orchid are a curious pale green color and are 2-4” long. Chadds Ford Atlantic ladies’-tresses thrives in full sun and moist to wet, acidic soils, yet it tolerates average, well-drained garden soils. It differs from the species in that it has larger and showier flowers. This terrestrial orchid performs best under low competition but is a good companion for bog-rosemary (Andromeda polifolia), pitcherplants (Sarracenia spp.), sand-swamp whitetop sedge (Rhynchospora latifolia), and cardinal flower (Lobelia cardinalis). Zones 5-8.
The taxonomy of this cultivar is debated. The ‘Chadds Ford’ cultivar was selected in the 1960s from a wild Spiranthes population located in Northern Delaware, just outside of Chadds Ford, Pennsylvania. At the time, the wild population was identified and recorded as nodding ladies’-tresses (Spiranthes cernua), a species that is rare in northern Delaware, but relatively common in Southern Delaware. For decades, ‘Chadds Ford’ was classified and sold as a cultivar of nodding ladies’-tresses, or less commonly fragrant ladies’-tresses (Spiranthes odorata), which is itself synonymous with Spiranthes cernua var. odorata.
Mt. Cuba Center formerly classified this cultivar as Chadds Ford nodding ladies-tresses (Spiranthes cernua ‘Chadds Ford’), but now supports new research that ‘Chadds Ford’ is a cultivar of Atlantic ladies’-tresses (Spiranthes bightensis). Atlantic ladies’-tresses is a recently describes species that is thought to be an ancient hybrid of S. cernua and S. odorata, having originated during a period when the ranges of those two species still overlapped (since then the range of S. odorata has shifted southward). The southernmost edge of the range of Spiranthes bightensis is north of the range of Spiranthes odorata and the two ranges do not overlap. The range of Spiranthes bightensis does overlap that of Spiranthes cernua however plants do not normally co-occur at the same location.
More Details
- Plant Type
perennial - Sun/Shade Conditions
full-sun-to-partial-shade - Foliage Character
evergreen - Soil Moisture
average-to-wet - Flowering Period
early-fall-to-frost - Soil PH
acidic - Flower Color
white - Summer Foliage Color
green - Other Scientific Names
Spiranthes cernua ‘Chadd’s Ford’, Spiranthes odorata ‘Chadd’s Ford’, Spiranthes cernua var. odorata ‘Chadds Ford‘
- Fall Foliage Color
green, yellow - Other Common Names
Chadds Ford nodding ladies'-tresses, Chadds Ford fragrant ladies'-tresses - Fruit/Seed Color
brown, tan
Additional Information
Flora of the Southeastern US, Missouri Botanical Garden , Plants of the Northeastern United States, NatureServe