Cochliasanthus

Cochliasanthus caracalla is a leguminous vine from the family Fabaceae, originating in tropical South America and Central America. The species is named caracalla, a corruption of the Portuguese caracol, meaning snail.[1][2]

Cochliasanthus caracalla
Vigna Caracalla 2.jpg
The curled flowers of C. caracalla
Scientific classification edit
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Fabales
Family: Fabaceae
Subfamily: Faboideae
Subtribe: Phaseolinae
Genus: Cochliasanthus
Trew
Species:
C. caracalla
Binomial name
Cochliasanthus caracalla
(L.) Trew
Synonyms
  • Vigna subg. Cochliasanthus (Trew) Verdc.
  • Phaseolus sect. Caracallae DC.
  • Vigna sect. Caracallae (DC.) Maréchal et al.
  • Vigna caracalla (L.) Verdc.
  • Cochliasanthus caracalla (L.) Trew

This perennial[3] vine (when grown in a climate without frost) has fragrant flowers said to be reminiscent of hyacinths - with a distinctive curled shape, giving rise to the common names corkscrew vine, snail vine, snail creeper, snailflower or snail bean. It is the only member of the genus Cochliasanthus and was formerly considered to belong to the genus Vigna.[4]

Two very different plant species are sold and cultivated under this one name. One plant is the true Cochliasanthus caracalla. The other, also called "Phaseolus giganteus" (a horticultural name, not validly published),[5] appears to be Vigna speciosa or a close relative. Thomas Jefferson called this plant "the most beautiful bean in the world".[3]

DescriptionEdit

The purple, non-fragrant, invasive flowers of the "Phaseolus giganteus" are said to have snail or snail-shell shaped flowers, hence the origin of the common name. The multicolored, fragrant, non-invasive flowers of the Cochliasanthus caracalla are said to have corkscrew or nautilus-shell shaped flowers, hence the origin of that common name. Though some claim that the leaves of one species are darker and differently sized compared to the leaves of the other, it is difficult to distinguish between these two plants through foliage alone.

There have been multiple instances where both plants have been grown side by side for years and the discovery that they were not the same species was made only after the less mature plant finally bloomed. It is said that both plants are pollinated by ants so, without ants, the plant will produce few, if any, seeds,[6][7] although C. caracalla is pollinated by bees in Argentine, which is its native range.[8]

Corkscrew vineEdit

 
Multicolored wavy flowers and spiral buds hanging in clusters
 
Wavy, purple-streaked white petals surrounded by immature, spiral-shaped buds of the same color.

The corkscrew vine, Cochliasanthus caracalla, has highly fragrant,[3][9] multicolored, corkscrew or spiral shaped flowers[10] and is not an invasive plant.

 
This image illustrates how truly unique the shape and colors of this plant's petals are.

More specifically, the flowers are white with purple streaks that fade to cream and then to yellow with age. They hang in twelve-inch long clusters.[11] The flowers are extremely wavy and immature blossoms very much resemble multicolored spirals or corkscrews. This plant grows white buds that produce nectar, which attracts ants, who then pollinate the flowers. The fragrance has been likened to Chinese wisteria, Jasmine, and Magnolia. It is claimed that the plant can be smelled from 15 feet away.[12] The Corkscrew Vine is less frost tolerant than the Snail Vine.[5]

Snail vineEdit

 
Snail Vine's flower

The snail vine, Phaseolus giganteus, is delightfully fragrant. [13] According to Baker Creek Rare Seeds, "This vining member of the bean family is one of the most intriguing plants that we’ve ever grown! The uniquely shaped flowers actually resemble small snails! The fragrance of these distinct blooms is thought to be reminiscent of hyacinths, and Thomas Jefferson called this plant 'The most beautiful bean in the world.' Perennial in its native region of Central and South America, snail vine is typically grown as an annual in areas that experience frost. We enjoyed an abundance of fragrant flowers all summer long, and are so excited to offer this incredible and wonderful vining plant! Rare and hard to find."

Flowers are a solid, pale purple. The flowers, which grow alone or in small groups[5] rather than in clusters, consist of four petals: one large wavy half-circle on the top, two tear-drop shaped petals that point inwards, and a thin, erect, curly petal sprouting from the center of the flower. Depending on the angle, the two bottom petals can appear to be a single petal that strongly resembles the large, upper petal. When this happens, the three main petals come together to form an open-clam shape. The center of the flower and the end of the thin, erect may have a small area of yellow and/or white but the color is usually faint and only noticeable upon close examination.

 
This invasive vine has taken over a fence and is now spreading across the ground.

Immature flower buds often form fat half-crescents but, unlike the corkscrew vine, these buds are green, yellow, or brown. This plant might be more susceptible to aphids but is definitely invasive and has been compared by multiple growers to kudzu. Rapid growth combined with the ability of vines touching the ground to take root make this an invasive plant.[14][15] This plant has been known to regrow even after all foliage visible above ground has died from frost.[15]

CultivationEdit

This vine is hardy in zones 9 and above, liking full sun and consistently damp soil. It prefers high heat and humidity. In colder zones, it does well in a pot if it is overwintered inside.

HarvestEdit

Flowers typically bloom in late summer or autumn[3][9] and, if pollination by bees[8] is successful, seeds come soon after. Seeds grow inside pods, like pea pods. If the grower wants to cultivate them, pods should be removed from the plant while still green to prevent exposure to winter temperatures. The seeds, which are technically beans, could be edible.[16] Parts of the true Corkscrew plant might be poisonous.[17]

 
Corkscrew vine seedpods

PreparationEdit

There is disagreement among growers on whether nicking the seed coat is more harmful or helpful to germination and some support nicking,[18] while others recommend against it. One widespread practice that does yield a high degree of success is to pour boiling water on the seeds and let the seeds soak overnight[18][19] in that water as it naturally cools to room temperature.

SowingEdit

Burpee recommends that the seeds be sown in "ordinary soil in a sunny area in spring after danger of frost" has passed. The seeds should be planted two to three inches apart and covered with half an inch of "fine soil". Burpee then recommends growers to "firm lightly" the soil and "keep evenly moist".[20]

The seedlings will sprout in one to three weeks depending on the weather. If grown indoors or inside a greenhouse, then the seedlings can be moved outdoors when "spring temperatures remain above 50 F."[11] These plants will thrive in full sun[3] to partial shade and can attain a height of twenty feet.[20]

Flowers can blossom during the same growing season that the seeds were planted in.[21] The plant blooms for as much as eight weeks.[20]

It is possible to grow both vine species from cuttings.[19]

ReferencesEdit

  1. ^ Giovanni Battista Triumfetti, Observationes de Ortu ac Vegetatione Plantarum (1685) pp.93-96
  2. ^ Paul Amman, Hortus Bosianus (1686) p. 27
  3. ^ a b c d e Monticello - Caracalla Bean. "Description, history, growth, and availability for sale"
  4. ^ Delgado-Salinas A, Thulin M, Pasquet R, Weeden N, Lavin M (2011). "Vigna (Leguminosae) sensu lato: the names and identities of the American segregate genera". Am J Bot. 98 (10): 1694–715. doi:10.3732/ajb.1100069. PMID 21980163.
  5. ^ a b c Almost Eden Snail Vine. "Description, growing, and sale information"
  6. ^ "Phaseolus giganteus, Snail vine -".
  7. ^ "Cochliasanthus caracalla, Vigna caracalla, Phaseolus caracalla, Corkscrew flower, Snail vine -".
  8. ^ a b Etcheverry, Angela Virginia; Alemán, Maria Mercedes; Fleming, Trinidad Figueroa (2008-06-28). "Flower Morphology, Pollination Biology and Mating System of the Complex Flower of Vigna caracalla (Fabaceae: Papilionoideae)". Annals of Botany. 102 (3): 305–316. doi:10.1093/aob/mcn106. ISSN 1095-8290. PMC 2701803. PMID 18587133.
  9. ^ a b Logee's Corkscrew Flower Archived 2014-01-23 at the Wayback Machine. "Care sheet"
  10. ^ Almost Eden Corkscrew Vine. "Description, growing, and sale information"
  11. ^ a b Park Seed - Fragrant Corkscrew Vine Seeds. "description, growth, sale"
  12. ^ "Corkscrew Vine or Snail Vine" Thomas Jefferson called this vine the most beautiful bean in the world. He had it grown at Monticello, and you can buy it from their gift shop as a certified plant from Jefferson's time.<https://www.monticelloshop.org/snail-flower-vigna-caracalla/> http://www.easytogrowbulbs.com/t-Corkscrew-Vine-or-Snail-Vine.aspx
  13. ^ [1]. "discusses characteristics of each in detail"
  14. ^ The Snail Vine - Confusion Reigns Supreme. "discusses characteristics of each in detail"
  15. ^ a b Desert Tropical - Snail Vine. "description"
  16. ^ "StackPath".
  17. ^ "Corkscrew Vine" http://www.easytogrowbulbs.com/p-1338-corkscrew-vine.aspx
  18. ^ a b How to Grow Cochliasanthus caracalla from Seed. "by Krystal Miller, Demand Media"
  19. ^ a b Growing information for Snail Vine.
  20. ^ a b c Burpee Vigna Corkscrew Archived 2014-01-02 at the Wayback Machine. "Growing Information"
  21. ^ "Archived copy". Archived from the original on 2014-01-02. Retrieved 2014-01-02.{{cite web}}: CS1 maint: archived copy as title (link)

External linksEdit