Verbena bonariensis
Encyclopedia
Verbena bonariensis is a member of the verbena family
(Verbenaceae
) cultivated as a garden annual or perennial. In horticulture
, it is also known by the ambiguous names "purpletop
" (also used for the grass
Tridens flavus
) and "South American vervain" (which can mean any of the numerous species
in the genus
Verbena
occurring in that continent). For the supposed common name "Brazilian Verbena" or "Brazilian Vervain", see below.
It is native to tropical
South America
where it grows throughout most of the warm regions, from Colombia
and Brazil
to Argentina
and Chile
.
.
Verbena bonariensis is a member of the South American vervains, which are polyploid
and have more than 14 chromosome
s. Among these, it is part of a lineage which might also include Verbena intermedia and seems well distant from Verbena litoralis
or Verbena montevidensis for example.
Sometimes, the common name "Verbena brasiliensis
, 'Brazilian Verbena' or 'Brazilian Vervain, is found for this species. However, this is the result of a mix-up with V. brasiliensis, the "true" Brazilian Verbena, which has been erroneously referred to as V. bonariaensis by several botanists.
Subspecies
There are two named subspecies
:
for traditional and drought tolerant and 'pollinator-host' garden
s and public landscape
s and park
s.
It is a tender perennial hardy in USDA Zones
7-11. It can be grown as an annual in areas where it is not winter hardy and will bloom in the first year when grown from seed. Its long internodes give it a sparse appearance but allow it to intermingle and coexist with other plants. The flowers are very attractive to butterflies
, and provide nectar for native bee
s and many beneficial garden insects.
This species grows best in a well-drained soil
. It prefers full sun to partial shade and needs regular moisture. It has a reputation of being rarely attacked by insect pests, but may be susceptible to powdery mildew
. V. bonariensis is commonly grown from seed which germinate readily without pre-treatment, but also can be propagated from herbaceous stem cuttings.
Verbena bonariensis is reportedly used as a veterinary
abortifacient
in Australia, although details are lacking.
and noxious weed in favorable habitat
s. It has naturalized in a number of southern U.S. state
s.
Presently, the plant is on the invasive species
watchlist for Washington State, naturalized in tropical and southern Africa
, temperate Asia
, Australia
, New Zealand
, the United States
(including Hawaiʻi
), the West Indies
, Macaronesia
and the Mascarene Islands
. According to Pacific Island Ecosystems at Risk, it is considered a weed in Fiji
, New Guinea
and other South Pacific islands.
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
(Verbenaceae
Verbenaceae
Verbenaceae, commonly known as the verbena family or vervain family, is a family of mainly tropical flowering plants. It contains trees, shrubs and herbs notable for heads, spikes, or clusters of small flowers, many of which have an aromatic smell.Recent phylogenetic studies have shown that...
) cultivated as a garden annual or perennial. In horticulture
Horticulture
Horticulture is the industry and science of plant cultivation including the process of preparing soil for the planting of seeds, tubers, or cuttings. Horticulturists work and conduct research in the disciplines of plant propagation and cultivation, crop production, plant breeding and genetic...
, it is also known by the ambiguous names "purpletop
Purpletop
Tridens flavus is a large, robust perennial bunchgrass native to North America. The seeds are purple, giving the grass its common name. The seeds are also oily, leading to its other common name, "greasegrass". It reproduces by seed and tillers. The grass is often confused with Johnson...
" (also used for the grass
Grass
Grasses, or more technically graminoids, are monocotyledonous, usually herbaceous plants with narrow leaves growing from the base. They include the "true grasses", of the Poaceae family, as well as the sedges and the rushes . The true grasses include cereals, bamboo and the grasses of lawns ...
Tridens flavus
Purpletop
Tridens flavus is a large, robust perennial bunchgrass native to North America. The seeds are purple, giving the grass its common name. The seeds are also oily, leading to its other common name, "greasegrass". It reproduces by seed and tillers. The grass is often confused with Johnson...
) and "South American vervain" (which can mean any of the numerous species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
in the genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
Verbena
Verbena
Verbena , verbenas or vervains, is a genus in the family Verbenaceae. It contains about 250 species of annual and perennial herbaceous or semi-woody flowering plants. The majority of the species are native to the New World from Canada south to southern Chile, but some are also native in the Old...
occurring in that continent). For the supposed common name "Brazilian Verbena" or "Brazilian Vervain", see below.
It is native to tropical
Tropics
The tropics is a region of the Earth surrounding the Equator. It is limited in latitude by the Tropic of Cancer in the northern hemisphere at approximately N and the Tropic of Capricorn in the southern hemisphere at S; these latitudes correspond to the axial tilt of the Earth...
South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
where it grows throughout most of the warm regions, from Colombia
Colombia
Colombia, officially the Republic of Colombia , is a unitary constitutional republic comprising thirty-two departments. The country is located in northwestern South America, bordered to the east by Venezuela and Brazil; to the south by Ecuador and Peru; to the north by the Caribbean Sea; to the...
and Brazil
Brazil
Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...
to Argentina
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...
and Chile
Chile
Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...
.
Description
Verbena bonariensis, Purpletop Vervain, is a tall and slender-stemmed perennial. It can grow to 6 ft (120 cm) tall and can spread to 3 ft (90 cm) wide. At maturity, it will develop a woody base. Fragrant lavender to rose-purple flowers are in tight clusters located on terminal and axillary stems, blooming from mid-summer until fall frost. The stem is square with very long internodes. Leaves are ovate to ovate-lanceolate with a toothed margin and grow up to 4 in (10 cm) long.Taxonomy and systematics
Its specific epithet refers to Buenos AiresBuenos Aires
Buenos Aires is the capital and largest city of Argentina, and the second-largest metropolitan area in South America, after São Paulo. It is located on the western shore of the estuary of the Río de la Plata, on the southeastern coast of the South American continent...
.
Verbena bonariensis is a member of the South American vervains, which are polyploid
Polyploidy
Polyploid is a term used to describe cells and organisms containing more than two paired sets of chromosomes. Most eukaryotic species are diploid, meaning they have two sets of chromosomes — one set inherited from each parent. However polyploidy is found in some organisms and is especially common...
and have more than 14 chromosome
Chromosome
A chromosome is an organized structure of DNA and protein found in cells. It is a single piece of coiled DNA containing many genes, regulatory elements and other nucleotide sequences. Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions.Chromosomes...
s. Among these, it is part of a lineage which might also include Verbena intermedia and seems well distant from Verbena litoralis
Verbena litoralis
Verbena litoralis is a species of verbena known by the common names seashore vervain and Brazilian vervain, and in Hawaiian, ōwī. It is native to the Americas from Mexico south through Central and South America to Argentina and Chile. It is present throughout the world as an introduced species and...
or Verbena montevidensis for example.
Sometimes, the common name "Verbena brasiliensis
Verbena brasiliensis
Brazilian Verbena or Brazilian Vervain, Verbena brasiliensis, is a flowering plant species from the vervain family...
, 'Brazilian Verbena' or 'Brazilian Vervain, is found for this species. However, this is the result of a mix-up with V. brasiliensis, the "true" Brazilian Verbena, which has been erroneously referred to as V. bonariaensis by several botanists.
Subspecies
There are two named subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
:
- Verbena bonariensis ssp. bonariensis L.
- Verbena bonariensis ssp. conglomerata Briq.
Cultivation
Verbena bonariensis, the tall, slender-stemmed Purpletop Vervain, is often cultivated by the plant nursery trade as an ornamental plantOrnamental plant
Ornamental plants are plants that are grown for decorative purposes in gardens and landscape design projects, as house plants, for cut flowers and specimen display...
for traditional and drought tolerant and 'pollinator-host' garden
Garden
A garden is a planned space, usually outdoors, set aside for the display, cultivation, and enjoyment of plants and other forms of nature. The garden can incorporate both natural and man-made materials. The most common form today is known as a residential garden, but the term garden has...
s and public landscape
Landscape design
Landscape design is an independent profession and a design and art tradition, practised by landscape designers, combining nature and culture. In contemporary practice landscape design bridges between landscape architecture and garden design.-Design scope:...
s and park
Park
A park is a protected area, in its natural or semi-natural state, or planted, and set aside for human recreation and enjoyment, or for the protection of wildlife or natural habitats. It may consist of rocks, soil, water, flora and fauna and grass areas. Many parks are legally protected by...
s.
It is a tender perennial hardy in USDA Zones
Hardiness zone
A hardiness zone is a geographically defined area in which a specific category of plant life is capable of growing, as defined by climatic conditions, including its ability to withstand the minimum temperatures of the zone...
7-11. It can be grown as an annual in areas where it is not winter hardy and will bloom in the first year when grown from seed. Its long internodes give it a sparse appearance but allow it to intermingle and coexist with other plants. The flowers are very attractive to butterflies
Butterfly
A butterfly is a mainly day-flying insect of the order Lepidoptera, which includes the butterflies and moths. Like other holometabolous insects, the butterfly's life cycle consists of four parts: egg, larva, pupa and adult. Most species are diurnal. Butterflies have large, often brightly coloured...
, and provide nectar for native bee
Bee
Bees are flying insects closely related to wasps and ants, and are known for their role in pollination and for producing honey and beeswax. Bees are a monophyletic lineage within the superfamily Apoidea, presently classified by the unranked taxon name Anthophila...
s and many beneficial garden insects.
This species grows best in a well-drained soil
Soil
Soil is a natural body consisting of layers of mineral constituents of variable thicknesses, which differ from the parent materials in their morphological, physical, chemical, and mineralogical characteristics...
. It prefers full sun to partial shade and needs regular moisture. It has a reputation of being rarely attacked by insect pests, but may be susceptible to powdery mildew
Powdery mildew
Powdery mildew is a fungal disease that affects a wide range of plants. Powdery mildew diseases are caused by many different species of fungi in the order Erysiphales. It is one of the easier diseases to spot, as its symptoms are quite distinctive. Infected plants display white powdery spots on the...
. V. bonariensis is commonly grown from seed which germinate readily without pre-treatment, but also can be propagated from herbaceous stem cuttings.
Verbena bonariensis is reportedly used as a veterinary
Veterinary medicine
Veterinary Medicine is the branch of science that deals with the prevention, diagnosis and treatment of disease, disorder and injury in non-human animals...
abortifacient
Abortifacient
An abortifacient is a substance that induces abortion. Abortifacients for animals that have mated undesirably are known as mismating shots....
in Australia, although details are lacking.
Invasive species
V. bonariensis self-seeds readily. This ability has raised concerns that it may become an invasive speciesInvasive species
"Invasive species", or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats, with several definitions....
and noxious weed in favorable habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
s. It has naturalized in a number of southern U.S. state
U.S. state
A U.S. state is any one of the 50 federated states of the United States of America that share sovereignty with the federal government. Because of this shared sovereignty, an American is a citizen both of the federal entity and of his or her state of domicile. Four states use the official title of...
s.
Presently, the plant is on the invasive species
Invasive species
"Invasive species", or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats, with several definitions....
watchlist for Washington State, naturalized in tropical and southern Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
, temperate Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
, Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
, New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
, the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
(including Hawaiʻi
Hawaii
Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...
), the West Indies
Caribbean
The Caribbean is a crescent-shaped group of islands more than 2,000 miles long separating the Gulf of Mexico and the Caribbean Sea, to the west and south, from the Atlantic Ocean, to the east and north...
, Macaronesia
Macaronesia
Macaronesia is a modern collective name for several groups of islands in the North Atlantic Ocean near Europe and North Africa belonging to three countries: Portugal, Spain, and Cape Verde...
and the Mascarene Islands
Mascarene Islands
The Mascarene Islands is a group of islands in the Indian Ocean east of Madagascar comprising Mauritius, Réunion, Rodrigues, Cargados Carajos shoals, plus the former islands of the Saya de Malha, Nazareth and Soudan banks...
. According to Pacific Island Ecosystems at Risk, it is considered a weed in Fiji
Fiji
Fiji , officially the Republic of Fiji , is an island nation in Melanesia in the South Pacific Ocean about northeast of New Zealand's North Island...
, New Guinea
New Guinea
New Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...
and other South Pacific islands.