Brunfelsia is a genus of approximately 50 species of shrubs, small trees, and rarely lianas in the nightshade family Solanaceae, subfamily Petunioideae. Native to the Neotropics — principally South America and the Caribbean — these plants inhabit light woodland and thickets, with one species, B. australis, ranging as far south as the Argentinian province of Buenos Aires.
Leaves are alternately arranged, simple, and usually oval. The flowers are salverform, with five broad lobes and a narrow tube, and are often fragrant. One of the most distinctive features of the genus is flower-color change: in cultivated species such as B. pauciflora, blooms open deep purple, then fade to lavender, and finally turn white over three days — the source of the popular common name "yesterday, today and tomorrow." Fruits are corky berries. The genus is also commonly called "raintree" and, for night-fragrant species, "lady of the night."
The genus was formally described by the French botanist Charles Plumier and published by Linnaeus in 1753, with B. americana as the type species. Linnaeus named it in honor of Otto Brunfels (1488–1534), an early German herbalist and theologian regarded as one of the "fathers of botany." Three sections are recognized within the genus: Brunfelsia (~22 species), Franciscea (~18 species), and Guianenses (~6 species).
All parts of Brunfelsia plants are toxic. The genus contains the alkaloid brunfelsamidine and, in some species, indole alkaloids related to DMT. Ingestion causes serious neurological symptoms in dogs, cats, and horses, including seizures, tremors, vomiting, and lack of coordination. Several species are widely cultivated as ornamentals in warm climates (USDA zones 9–11), valued for their fragrant, color-changing flowers and, in the case of B. australis, drought tolerance.
Etymology
The genus name Brunfelsia was coined by Carl Linnaeus in 1753 to honor Otto Brunfels (1488–1534), a German theologian, herbalist, and physician who is counted among the founding figures of modern botany. Linnaeus built on the earlier work of the French botanist Charles Plumier, who had first described the genus. The species epithet of the most widely cultivated member, B. pauciflora, means "few-flowered" in Latin.
Distribution
Brunfelsia is entirely neotropical in natural distribution, with species native to South America and the Caribbean. The genus spans tropical and subtropical habitats from the Antilles and Central America through the Amazon basin, the Atlantic Forest of Brazil, the Andean foothills, and into the Southern Cone. Brunfelsia australis reaches the southernmost limit of the genus, occurring in the Argentinian province of Buenos Aires. Herbarium collections document species across the breadth of the Western Hemisphere tropics, including representatives from Bolivia, Brazil, Colombia, Ecuador, Jamaica, Peru, Puerto Rico, and Trinidad.
Ecology
In the wild, Brunfelsia species grow in light woodland and thickets. Many are semi-evergreen, retaining foliage through dry seasons. The flowers are highly fragrant, particularly at night in some species, which suggests pollination by moths or other nocturnal insects. In cultivation, species attract butterflies and other pollinators. Plants are generally adapted to humid tropical and subtropical conditions and, in the case of B. australis, can tolerate periodic drought.
Cultivation
Brunfelsia species are grown as ornamental shrubs in warm climates, principally in USDA hardiness zones 9–11. They perform best in full sun to partial shade with moist, humus-rich, acidic soil (pH below 6.0) and a humid environment. Growth rate is slow; mature plants typically reach 3–8 feet in height and 4–6 feet in spread. In cooler climates they are grown as container specimens and brought indoors during winter, where they require at least three hours of sunlight daily and consistently moist (but not waterlogged) soil.
Brunfelsia australis has been particularly promoted by growers for its tricolored display and drought resistance. All species benefit from regular pruning to encourage flowering; heavier pruning in autumn helps shape the plant and promotes the following season's bloom. Plants are deer-resistant and serve well as specimen plants, informal hedges, screens, or large container subjects.
Propagation
Brunfelsia is propagated from softwood cuttings. Pruning after the main flowering flush — with a heavier cut in autumn — both shapes the plant and stimulates new growth that will carry the next season's flowers.
Conservation
In Louisiana (USA), the cultivation or possession of Brunfelsia species is restricted to ornamental purposes under State Act 159, reflecting concern about the alkaloid content of some species and their potential for misuse.
Cultural Uses & Toxicity
All parts of Brunfelsia plants are poisonous if ingested, with the berries being especially hazardous. The genus contains brunfelsamidine, a strychnine-like alkaloid, and in some species indole alkaloids including DMT derivatives. In pets, ingestion causes a characteristic multi-day syndrome: tremors, prolonged seizures, vomiting, diarrhea, excessive drooling, lethargy, incoordination, and coughing. Dogs, cats, and horses are all susceptible. Contact with foliage can cause dermatitis in sensitive individuals. Because of the neurological severity and multi-day duration of symptoms, veterinary attention is recommended immediately upon suspected ingestion.
In some Amazonian traditions, species such as B. grandiflora (chiricaspi) and B. chiricaspi have been used in shamanic and medicinal contexts, owing to their psychoactive alkaloid content.
Taxonomy
The genus Brunfelsia L. (1753) is placed in the family Solanaceae (nightshade family), subfamily Petunioideae, order Solanales. Linnaeus formally published the genus in Genera Plantarum (ed. 1, p. 332) using prior descriptive work by Charles Plumier. The type species is Brunfelsia americana.
Three sections are currently recognized: sect. Brunfelsia (~22 species), sect. Franciscea (~18 species), and sect. Guianenses (~6 species), totaling approximately 50 accepted species. GBIF records 78 descendant taxa (including synonyms). SEINet herbarium collections document 37 named species. Taxonomic status of the genus is universally accepted with no nomenclatural disputes at genus rank.
