Plant of the Week: Slender Ladies' Tresses (Green Pearl Twist)
The University of Arkansas System Division of Agriculture does not promote, support or recommend plants featured in "Plant of the Week." Please consult your local Extension office for plants suitable for your region.
Plant of the Week
Slender Ladies' Tresses, Green Pearl Twist
Latin: Spiranthes lacera var. gracilis
In the Victorian era, ladies and gentlemen spent a great deal of time and energy getting
to know nature up close and personal. This quaint trait has largely disappeared from
our society. Relatively few people know much about the natural world in which we live.
A lawn here in Fayetteville is populated with Ladies’ Tresses Orchids. Every fall, just as the flowers attain full bloom, the lawn is mowed to remove these spiky "weeds" that suddenly spring from the ground in late summer. A proper Victorian lady would have known her wildflowers and cherished her good fortune.
The Spiranthes orchids are not your typical orchid, and it is not surprising that people don’t readily recognize them as such. They grow about 18-inches tall on slender stems that have a peculiar twisted inflorescence on the top third of the stem. The Latin name means "twisted flower," an apt description for the group.
The white flowers are about a quarter of an inch long with five petal-like tepals closely appressed to the slightly inflated lip that’s marked with green inside. The lip is ruffled at the end. Open flowers first appear at the base of the spike and open spirally up the stem as blooming progresses. Individual plants are in flower for about two to three weeks, usually in late August or early September.
The leaves appear in the spring in a basal whorl from the three fleshy roots that attach to the subterranean crown. Leaves are 1-2 inches long and about half as wide. At the time of flowering, the leaves are done for the year and wither away.
This genus of terrestrial orchids is cosmopolitan, with over 200 species described worldwide. Slender Ladies’ Tresses are one of the most common species in the genus. They’re found throughout the southeastern states with scattered stands as far north as southern Canada. They usually occur in dry, upland soils with an acidic pH and are associated with open glades in the hickory-oak forest or oak-pine forests.
Bumble bees are thought to be the main pollinators of the species. Of all the native terrestrial orchids, this group seems to reproduce more freely by seed than other species. It will migrate into disturbed sites and is sometimes seen on roadsides.
A few specialist growers carry Spiranthes orchids in their catalogs, but only S. cernua f. odorata ‘Chadd’s Ford’ can be considered remotely common even in the specialty trade. This species is distributed more in the upper Midwest and the East and differs by having stouter stems, somewhat larger flowers and a prominent lip.
This cultivar also has a spicy sweet fragrance that is an added bonus. It was rescued from a roadway construction site in Delaware and apparently spreads by underground runners, making commercial propagation possible. It’s best used in a slightly moist, highly organic soil that’s shaded during the hottest part of the day. An area receiving morning sun and afternoon shade is ideal.
By: Gerald Klingaman, retired
Extension Horticulturist - Ornamentals
Extension News - August 4, 2000
The University of Arkansas Division of Agriculture does not maintain lists of retail outlets where these plants can be purchased. Please check your local nursery or other retail outlets to ask about the availability of these plants for your growing area.