Wisteria is a genus of flowering plants in the pea family, Fabaceae, that includes ten
species of woody climbing vines native to the Eastern United States and to China, Korea,
and Japan. Some species are popular ornamental plants, especially in China and Japan. An
aquatic flowering plant with the common name wisteria or 'water wisteria' is in fact Hygrophila
difformis, in the family Acanthaceae.
Taxonomy The botanist Thomas Nuttall said he named
the genus Wisteria in memory of Dr. Caspar Wistar. Questioned about the spelling later,
Nuttall said it was for "euphony," but his biographer speculated that it may have something
to do with Nuttall's friend Charles Jones Wister, Sr., of Grumblethorpe, the grandson
of the merchant John Wister. As the spelling is apparently deliberate, there is no justification
for changing the genus name under the International Code of Botanical Nomenclature. However, some
spell the plant's common name "wistaria", and Fowler is decisively for the "wistaria"
spelling. Genetic analysis shows Callerya, Afgekia and
Wisteria to be each other's closest relatives and quite distinct from other members of the
tribe Millettieae. Both have eight chromosomes. Species
Wisteria brachybotrys Siebold & Zucc. Wisteria brevidentata Rehder
Wisteria floribunda DC. – Japanese Wisteria Wisteria frutescens Poir. – American Wisteria
Wisteria macrostachya Nutt. ex BL Robins. & Fern. – Kentucky Wisteria
Wisteria sinensis DC. – Chinese Wisteria Wisteria venusta Rehder & Wils. – Silky
Wisteria Wisteria villosa Rehder
Description Wisteria vines climb by twining their stems
either clockwise or counterclockwise round any available support. They can climb as high
as 20 m above the ground and spread out 10 m laterally. The world's largest known Wisteria
vine is in Sierra Madre, California, measuring more than 1 acre in size and weighing 250
tons. Planted in 1894, it is of the Chinese lavender variety.
The leaves are alternate, 15 to 35 cm long, pinnate, with 9 to 19 leaflets. The flowers
are produced in pendulous racemes 10 to 80 cm long, similar to those of the genus Laburnum,
but are purple, violet, pink or white. There is no yellow on the leaves. Flowering is in
the spring in some Asian species, and in mid to late summer in the American species and
W. japonica. The flowers of some species are fragrant, most notably Chinese Wisteria. The
seeds are produced in pods similar to those of Laburnum, and, like the seeds of that genus,
are poisonous. Wisteria is an extremely hardy plant that
is considered an invasive species in many parts of the U.S., especially the Southeast,
due to its ability to overtake and choke out other native plant species.
Wisteria species are used as food plants by the larvae of some Lepidoptera species including
brown-tail. Cultivation
Wisteria, especially Wisteria sinensis, is very hardy and fast-growing. It can grow in
fairly poor-quality soils, but prefers fertile, moist, well-drained soil. They thrive in full
sun. Wisteria can be propagated via hardwood cutting, softwood cuttings, or seed. However,
specimens grown from seed can take decades to bloom; for this reason, gardeners usually
grow plants that have been started from rooted cuttings or grafted cultivars known to flower
well. Another reason for failure to bloom can be excessive fertilizer. Wisteria has
nitrogen fixing capability, and thus mature plants may benefit from added potassium and
phosphate, but not nitrogen. Finally, wisteria can be reluctant to bloom because it has not
reached maturity. Maturation may require only a few years, as in Kentucky Wisteria, or nearly
twenty, as in Chinese Wisteria. Maturation can be forced by physically abusing the main
trunk, root pruning, or drought stress. Wisteria can grow into a mound when unsupported,
but is at its best when allowed to clamber up a tree, pergola, wall, or other supporting
structure. Whatever the case, the support must be very sturdy, because mature Wisteria
can become immensely strong with heavy wrist-thick trunks and stems. These will certainly rend
latticework, crush thin wooden posts, and can even strangle large trees. Wisteria allowed
to grow on houses can cause damage to gutters, downspouts, and similar structures. Its pendulous
racemes are best viewed from below. Wisteria flowers develop in buds near the
base of the previous year's growth, so pruning back side shoots to the basal few buds in
early spring can enhance the visibility of the flowers. If it is desired to control the
size of the plant, the side shoots can be shortened to between 20 and 40 cm long in
mid summer, and back to 10 to 20 cm in the fall. Once the plant is a few years old, a
relatively compact, free-flowering form can be achieved by pruning off the new tendrils
three times during the growing season; in June, July and August, for the northern hemisphere.
The flowers of some varieties are edible, and can even be used to make wine. Others
are said to be toxic. Careful identification by an expert is strongly recommended before
consuming this or any wild plant. In culture
Fuji Musumè or Wisteria Maiden is an Otsu-e subject thought to have been inspired by popular
dances. These paintings were often sold as good-luck charms for marriages. Fuji Musumè
is also a famous classical Kabuki dance. In Barbara Kingsolver's novel The Bean Trees,
Turtle refers to wisteria vines as bean trees, because the pre-bloomed flower pods are shaped
like beans. Later, she and Taylor learn that wisteria is a legume and that wisteria and
other legumes engage in symbiotic relationships, just as the book's characters do.
See also List of Special Places of Scenic Beauty, Special
Historic Sites and Special Natural Monuments References
External links Ohio State University fact sheet on wisteria
Wistaria Festival, Sierra Madre, California Texts on Wikisource:
"Wistaria". The American Cyclopædia. 1879. "Wistaria". New International Encyclopedia.
1905. "Wistaria". Collier's New Encyclopedia. 1921.