Wisteria frutescens isteria frutescens is a woody liana, generally range through shades of violet and Wpotentially growing to heights of 15 m; blue, with stronger reddish tones in the calyx young stems are smooth or covered with small and newly opened petals, and darker petal hairs pressed tightly to the stem surface. Stems veins; further, standard petals bear a triangular climb by twining around supports in a clockwise yellowish central zone; white-flowered variants direction. Leaves are alternate and odd-pinnately are known. Stamens are fully enclosed by the compound, 10—30 cm long. Leaves may have paired keel petals; nine of the ten stamens have from 5 to 15 leaflets that are elliptic to lance- filaments fused tube-like with the tenth stamen ovate in shape with acute to acuminate tips; separate from the rest. Ovaries are solitary leaflets are pubescent upon emergence in spring per flower, enclosed by the keel petals, and but become hairless as the season progresses. surrounded by staminal filaments; ovaries are Name & Relationships Densely flowered terminal racemes appear in late stalked at the base and bear numerous ovules. isteria species are members of the large spring well after the appearance of leaves and Fruits (“legumes”) are elongate, linear, smooth, Wand diverse family known as legumes sporadically throughout the summer; racemes capsules bearing multiple reniform seeds. (Fabaceae). American Wisteria is the first species range from 3 to 15 cm in length. Flowers conform of the genus to receive a formal scientific name, with the general pattern of papillionoid legumes, In the Garden Glycine frutescens, in the 1753 Species Plantarum merican Wisteria is a plant of easy garden however, since the racemes are pendulous, of Linnaeus. In 1818, Thomas Nuttall recognized culture; for best results provide a location individual flowers appear upside down relative A this woody liana as distinct from Soybeans; in full or nearly full sun and water regularly to most such legumes. Sepals are fused into a Nuttall’s genus name, Wisteria, commemorates during dry spells; it is hardy in USDA Zones 5 cup-like calyx 5—7 mm long, the rim of which Caspar Wistar, late 18th/early 19th C physician through 9. It can be grown to flowering size in is irregularly and shallowly lobed. There is a and anatomist from Philadelphia. The species containers if provided with a trellis for support. single standard petal that reflexes backward portion of the scientific name, frutescens, Regular pruning is recommended to control long and forms a broad means shrubby. There are seven or eight species whip-like branches that develop by late summer. semicircle 1.5 to classified in the genus Wisteria; two species are Wisteria frutescens is often recommended as a 2 cm in diameter; native to eastern North America; the remainder native substitute for commonly cultivated Asian paired wing petals are from eastern Asia. species: Chinese Wisteria (W. sinensis), Japanese are obovate and Wisteria (W. floribunda) or their all-too- Human Uses converge at their frequently encountered spontaneous hybrid, umerous sources suggest eating Wisteria tips; two keel W. x formosa; these Asian Wisterias are widely flowers in salads or extracting them via cold petals curve N considered to be aggressively invasive. Wisteria water to produce a cooling beverage. Caution, downward and frutescens can be propagated by seeds sown however, is advised because Wisteria species terminate under in fall or spring with no special pre-treatment do contain several known toxins. Roots, bark, the tips of the needed, or by means of softwood cuttings taken branches, fruits, and seeds contain triterpene-based wingpetals. in the spring. The most readily available cultivar saponins that will cause gastro-intestinal distress. Flower colors is ‘Amethyst Falls,’ selected from a wild source Seeds also contain canavanine, a molecule that, are subtly and noted for vivid lavender flowers and reliable if ingested, can disrupt the synthesis of proteins, variable, but flower production in young plants. resulting in impairment of multiple life processes. In the Wild Conservation Status American atural populations of Wisteria frutescens he Virginia Division of Natural Heritage Ninhabit coastal plain swamp forests, Tcharacterizes the conservation status of streamsides, and woodland margins, from Wisteria frutescens as G5, S1, meaning that Wisteria southeast Virginia to Florida and Alabama. the species is considered secure given its American Wisteria is the larval host for Long- abundance throughout its entire geographic Wisteria frutescens tailed Skippers, Silver-spotted Skippers, Marine range, but critically imperiled in Virginia where Blue, and Zarucco Duskywing Butterflies. the species occurs at the northern fringe of Flowers are attractive to a variety of adult that range. butterfly species as well as long-tongued bees and hummingbirds.

American Wisteria Compound Leaf

Gardeners should not collect American Wisteria in the wild and should be certain that all native plants purchased for home gardens have been nursery-propagated, not wild- collected. To learn more about interesting Where to See It species of plants native to Virginia, visit www. side from cultivated specimens, which vnps.org for times and dates of programs and 2021 A can be found in many public and private wildflower walks in your area, and for sources gardens, wild plants of Wisteria frutescens of nursery-propagated plants. occur in scattered localities found in just nine Virginia Native Plant Society counties of southeast Virginia. Blandy Experimental Farm 400 Blandy Farm Lane, Unit 2 Boyce, VA 22620 Wisteria frutescens [email protected] Virginia Wildflower 540-837-1600 Text by W. John Hayden, VNPS Botany Chair of the Year Color illustration by Elena Maza Borkland Pen-and-ink illustration by Nicky Staunton Color photos by Su Kim From the Digital Atlas of the Virginia Flora, vaplantatlas.org Layout by Nancy Sorrells WWW.VNPS.ORG