Petunioideae

The genera Brunfelsia, Plowmania, Fabiana, Nierembergia and Petunia furnish garden plants bearing attractive flowers. Brunfelsia and Plowmania are genera of tropical shrubs requiring glasshouse protection in temperate climate areas; Fabiana species are hardy shrubs; Nierembergia species are dwarf, hardy herbaceous perennials or sub-shrubs, and Petunia × atkinsiana has yielded a huge variety of flower colours, forms and patterns that have made it a favourite summer bedding plant. Petunia is by far the best-known genus of the subfamily in popular temperate zone horticulture.[10]

Brunfelsia pauciflora - Brazilian species, grown as pot-plant in glasshouse, Chelsea Physic Garden

Fabiana imbricata (Chilean vernacular name pichi) is used as a diuretic and digestive in the folk medicine of Chile. Studies have revealed it to contain sesquiterpenes possessing gastroprotective properties.[11]

A number of Brunfelsia species have played important roles in the folk medicine of peoples indigenous to South America, having been used to treat conditions as diverse as syphilis, rheumatism, yellow fever and snakebite. The roots are the most effective parts of the plants and possess diuretic and sweat-inducing properties. Medications prepared from Brunfelsia species have the curious effect of producing the sensation of chills, this being the rationale for their folk use in the treatment of fevers.[12]

Species belonging to the genera Brunfelsia, and Petunia have been employed as entheogens in South America,[12] while the species Nierembergia hippomanica has been reported to have toxic and hallucinogen-like effects upon horses and to have similarities in its chemistry to that of the genus Brunfelsia.[13][14][15]The chemistry of Nierembergia hippomanica is most unusual for that of a plant belonging to the Solanaceae, in that the species contains (among other classes of toxic compounds) phenethylamine proto-alkaloids more usually associated with cacti and grasses: β-Phenylethylamine, N-Methyltyramine, tyramine, and hordenine have been isolated from it.[16]

The unusual epithet hippomanica is a compound of the Greek elements ἵππος ("hippos") horse and μανία ("mania") insanity / frenzy – hence "sending horses insane". Botanist John Miers references in the species name a plant hippomanes of uncertain identity mentioned in the idyll of Theocritus and the works of Theophrastus – so called either because horses were madly fond of it, or because it sent them mad if they fed upon it. The Greek name hippomanes was also referenced in the creation of the genus name Hippomane for an extremely toxic genus in the Euphorbiaceae.[17]

Petunia violacea Lindl. has been reported to be used as a hallucinogen in Ecuador, where it has the vernacular name shanín. The drug is said to cause sensations of levitation and flight – a type of hallucination often associated with the use of the more toxic hallucinogenic plants of the deliriant type, e.g. the tropane-containing Atropa and Hyoscyamus – active constituents of the witches' flying ointments.[18]

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  Benthamiella patagonica, a highly ornamental, caespitose hardy alpine from Patagonia.
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  Brunfelsia australis: part of the ornamental value of Brunfelsia lies in the colour changes occurring in the flowers as they age.
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  Fabiana imbricata f. violacea: the curious genus Fabiana includes species bearing a remarkable likeness to plants of the unrelated genus Erica.
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  Growth habit of Fabiana imbricata, showing similarity to that of the Erica arborea.
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  Nierembergia scoparia the broom-leaved cup flower, an attractive ornamental.
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  Nierembergia repens the creeping cup flower, a dwarf hardy perennial with large flowers – relative to its size.
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  Calibrachoa parviflora: tiny flower and much-reduced hairy leaves seen in extreme close-up.
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  Petunia axillaris: one of the two parent species of the popular summer bedding plant Petunia × atkinsiana.