Sinningia is a genus in the Gesneriaceae family that is mostly tuberous -- although some species are fibrous-rooted shrubs and some produce only rudimentary tubers. A few species are "stoloniferous," producing satellite tubers (e.g., S. tubiflora), and most species are lithophytes (growing on rocks) or epiphytes, rather than truly terrestrial. With over 70 species, the genus spans from Central America all the way south to Argentina; however, the largest concentration of species are found in eastern and southern Brazil, where they grow in both the humid Atlantic rainforest and the rocky savannah known as "campos rupestres." To this genus belongs the common florist "gloxinia" (S. speciosa), as well as some miniature species (S. pusilla, S. concinna and the newly discovered S. sp. "Rio das Pedras"), and S. leucotricha, which is well sought after by growers of succulents (unfortunately, this latter plant is often grown erroneously as S. canescens, a different species). Many plants in the genus make attractive houseplants or garden subjects, and those from southern Brazil and Argentina specially have proven to be hardy to zone 7 (or even 6) in the U.S. In addition to attractive flowers, some species are grown for their beautiful pubescent haired leaves (S. leucotricha, S. hatschbachii, S. canescens, S. globulosa). Succulent growers also grow many species, particularly those with large exposed tubers (such as S. bulbosa, S. macrostachya, S. lineata). Flower color is mostly red, although some species have orange, yellowish, lavender-purple, green and white flowers (with or without spots). A few species also have fragrant flowers (in particular, S. tubiflora, and some clones of S. speciosa, S. lindleyi and S. guttata). (by Tsuh Yang Chen, updated June 2009)
Information about hybrids and pictures of them can be found on the Sinningia Hybrids wiki page.
Sinningia aggregata is native to Brazil. Joseph Theunissen photographed it and reported: "During a trip through Brasil I found between Santos and São Paulo a Sinningia with long upstanding branches. The leaves are like velvet and when you rub a leaf it smells like citron." Members of the gersneriphiles list identify this as S. aggregata. It has a range of flower colors and a habit closely resembling that in the picture. Its leaves are often fragrant, although one source characterizes the texture as "sticky", not velvet. The geographical range of Sinningia aggregata includes Paraná, Santa Catarina, and São Paulo states in Brazil (information courtesy of Gesneriad World Checklist). The lemony fragrance is also characteristic.
Sinningia aghensis is a very tall species with red-wine colored flowers atop tall peduncles. Photo 1 was taken was taken in situ, in Brazil by Tsuh Yang Chen. Photos 2-4 show the flowers in detail and the habit (grown by/photos by Alan Lavergne).
Sinningia iarae is a relatively new comer to the collector world. It was discovered a few years ago. S. iarae has proven to be hardy in NC and has been used extensively in a lot of primary hybrids in hopes of increasing color range. Photo by John Ingram.
Sinningia leucotricha is a great garden plant for So. Cal. and can be grown in full sun along the coast. This is one of the most common species grown, sometimes mistakingly sold as canescens. It does fine with afternoon shade elsewhere. The salmon color is great and the fuzzy white leaves are a treasure. It is quite often sold by succulent growers because of the exposed caudex which can be quite attractive. The flowers are a beautiful salmon and open before the leaves are fully formed. These small leaves will expand over a month or so to reach 6-8" long. The first photo was taken by John Ingram and the next two by Bill Dijk. The third picture was taken three weeks after the second.
Sinningia macrostachya is a large leaf plant with few flowers. I want to use this in some hybrids to increase plant size. The leaves can reach 10" across each and have the feel of sandpaper. It is quite interesting. Photo by John Ingram.
Sinningia magnifica This is a beautiful blooming specimen. I have tried crossing this with a few other species to see what I will get. The first photo was taken by John Ingram and the second by Tsuh Yang Chen in situ in Brazil.
A picture of the plant in the wild was taken in October of 2003 at Iguazú Falls, Argentina, by Mark Wilcox.
Sinningia stricta is a plant with big tubers, and pale red flowers visited by hummingbirds. Picture from the northeast of Argentina, by Germán Roitman. Note from John Ingram, S. stricta is a synonym for S. elatior. Also, this photo looks a lot like what should be labeled as S. warmingii. So, the plot thickens. S. warmingii has straight corollas while S. elatior is dorsally curved.
Sinningia tubiflora is a lovely tuberous species that produces long tubular flowers with a lovely delicate sweet perfume, reminiscent of 'Froot Loops' cereal. In contrast to the lovely fragrant flowers, the foliage smells foul when bruised. The species is somewhat hardy and can survive to -6 °C frost in Canberra, Australia and can be grown in sheltered areas of USDA zone 6. It can be grown very easily in the ground, going dormant each winter and then re-sprouting with blooms in early summer. Plant the tubers in an area that gets full sun and lots of heat. They didn't seem to mind winter rainfall as long as the soil was well drained. The plants need a cool winter dormancy (lower than 15 °C) in order to bloom the following year. In warm climates such as Honolulu, Hawai`i this species remains evergreen and vigorous yet fails to reflower. It is probably best to allow the foliage to dry out before removing the stems from the plant. This species blooms in summer atop new growth that emerges in late spring (Jacob Uluwehi Knecht). It can good number of tubers and form nice colonies over time (John Ingram).
Photos 1-2 were taken by Paul Tyerman. Photo 3 was taken by John Ingram. Photos 4-6 were taken by Jacob Uluwehi Knecht. Photo 4 shows the fuzzy leaves as they break dormancy. Photo 5 offers a side view of the flower and photo 6 shows a direct frontal view.
More information on this genus as well as pictures can be found on the Gesneriad Reference Web