Tradescantia pallida

Tradescantia pallida
Tradescantia pallida 'Purpurea'
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Clade: Commelinids
Order: Commelinales
Family: Commelinaceae
Genus: Tradescantia
Species:
T. pallida
Binomial name
Tradescantia pallida
Synonyms[1]

Setcreasea pallida Rose
Setcreasea purpurea Boom

Tradescantia pallida is a species of spiderwort native to the Gulf Coast region of eastern Mexico. It is a perennial herbaceous species with a trailing habit. The cultivar T. pallida 'Purpurea', commonly called purple heart or purple queen, is widely grown as a houseplant, outdoor container plant, or a garden groundcover. The species has been proven useful in indicating and removing air and soil pollutants and has also been used in food technology.

Taxonomy

T. pallida is a species of spiderwort in the family Commelinaceae.[2] The type specimen was collected by Edward Palmer, one of the main US plant collectors of his time, in the Mexican state of Tamaulipas (possibly near Ciudad Victoria[3]) in 1907.[4] The species was described by Joseph Nelson Rose in 1911. He placed it in the genus Setcreasea. In 1975 David Hunt transferred the species to the genus Tradescantia.[2] Hunt also treated Setcreasea purpurea as a cultivar of S. pallida.[3] The latter names are still often used to refer to T. pallida.[2] The specific epithet pallida means "pale", referring to the original color of the leaves.[4]

The plant is known by several common names, including purple heart (probably in reference to the eponymous military medal[4]) and purple wandering jew.[2]

Description

T. pallida is perennial and herbaceous. It has a rambling habit, with plants reaching about a 1 ft (30 cm) in height but spreading considerably wider:[2] the stems may trail to 18 in (46 cm) or more.[5] Wild specimens are gray-green-purplish with a washed out look.[4]

Flower of T. pallida 'Purpurea'

The fleshy, hairy leaves are up to 7 in (180 mm) long,[2] narrow-oblong, and v-shaped.[5] and form a sheath around fleshy stems, which break off easily. On the ends of the stems the plants produce relatively inconspicuous flowers. The flowers are three-petaled as is typical for the Tradescantia genus. The flowering is most abundant from midsummer through fall and sporadic at other times of the year.[2] The flowers are open only in the morning.[4] The plants are evergreen,[4] but in colder areas die back to the ground in winter and resprout from the roots in spring.[2]

Distribution and habitat

T. pallida is found along the coast of the Gulf of Mexico. Its native range extends from Tamaulipas to Yucatan.[4] The species has been collected in a tropical deciduous forest, among roadside limestone rocks, and on limestone outcrops.[3]

Uses

T. pallida 'Purpurea' as a houseplant

T. pallida is grown as an ornamental plant for its attractive foliage.[2] Only the cultivar 'Purpurea', featuring purple-violet leaves and stems,[5] is commercially grown.[4] 'Purpurea' is sometimes sold under the name 'Purple Heart',[5] and has gained the Royal Horticultural Society's Award of Garden Merit.[6]

T. pallida is a popular groundcover plant in tropical and semi-tropical areas. In temperate climates it has traditionally been used as a houseplant but is increasingly being planted outdoors in containers or as a groundcover. It is also suitable for hanging baskets, border fronts, and rock gardens.[5] The plant is hardy down to USDA zone 7.[2] It may be grown in the shade but the most intense purple color is achieved in full sun.[2][4][5] The plant is remarkable for easily tolerating both drought[2][4][5] and frequent watering.[2] It is generally not affected by pests or diseases; however, slugs and caterpillars may attack young shoots of outdoor specimens, while houseplants should be monitored for aphids and scale.[5]

T. pallida has been proven useful for phytoremediation, biomonitoring, and genotoxicity assessment of environmental pollutants, especially heavy metals and metalloids from coal power plants.[7] As a houseplant, T. pallida has been judged exceptionally effective at improving indoor air quality by filtering out volatile organic compounds, a class of common pollutants and respiratory irritants.[8]

Because the plant contains anthocyanins, T. pallida leaves have been used as food colorants[9][10] and food preservatives.[10]

References

  1. ^ "Tradescantia pallida". Germplasm Resources Information Network. Agricultural Research Service, United States Department of Agriculture. Retrieved 2011-11-20.
  2. ^ a b c d e f g h i j k l m Mahr, Susan. "Purple Heart, Tradescantia pallida". University of Wisconsin. Retrieved 29 September 2024.
  3. ^ a b c "The Reunion of Setcreasea and Separotheca with Tradescantia". American Commelinaceae: I. 30 (3). Kew Bulletin: 443–458. 1975. JSTOR 4103068. Retrieved 29 September 2024.
  4. ^ a b c d e f g h i j Klingaman, Gerald (21 October 2016). "Plant of the Week: Tradescantia pallida, Purple Heart". University of Arkansas. Retrieved 29 September 2024.
  5. ^ a b c d e f g h "Tradescantia pallida 'Purpurea'". Missouri Botanical Garden. Retrieved 29 September 2024.
  6. ^ "Tradescantia pallida 'Purpurea'". RHS. Retrieved 5 March 2021.
  7. ^ Meravi, Neelima; Prajapati, Santosh Kumar (2014). "Biomonitoring the Genotoxicity of Heavy Metals/Metalloids Present in Soil Contaminated by Fly Ash from Coal-Fired Thermal Power Plant Using Tradescantia pallida". Phytoremediation. 1. Springer: 173. ISBN 978-3319103952.
  8. ^ Yang, Dong Sik; Pennisi, Svoboda V.; Son, Ki-Cheol; Kays, Stanley J. (1 August 2009). "Screening Indoor Plants for Volatile Organic Pollutant Removal Efficiency". HortScience. 44 (5): 1377–1381. doi:10.21273/HORTSCI.44.5.1377.
  9. ^ Houghton, J.D.; Hendry, G.A.F. (2012). Natural Food Colorants. Springer Science & Business Media. ISBN 978-1461521556.
  10. ^ a b Imtiaz, Fariha; Islam, Muhammad; Saeed, Hamid; Ahmed, Abrar; Rathore, Hassaan Anwer (1 March 2023). "Assessment of the antidiabetic potential of extract and novel phytoniosomes formulation of Tradescantia pallida leaves in the alloxan-induced diabetic mouse model". FASEB Journal. 37 (4). doi:10.1096/fj.202201395RR.