Sunburst bromeliads - Sincoraeas from Bahia, Brazil
Terrestrial bromeliads of the genus Sincoraea (formerly Orthophytum) with nested/sessile inflorescences are spectacular in flower and very rewarding plants for the succulent grower. They originate from the plateaus and foothills of the Chapada Diamantina in Bahia, Brazil, where they are commonly known as "Raio de Sol" or "Sunburst" bromeliads. In 2010, Rafael Louzada and Maria da Gracas Lapa Wanderley published a monograph in "Phytotaxa" on this group of plants that provided a detailed, well- illustrated description and key to 13 species. Subsequently, at least one new species of this group has been described and it appears likely that others remain undescribed. It is also probable that there are natural hybrids between several of the species. Of the species currently accepted by taxonomists, about a dozen are in cultivation outside of Brazil although only Sincoraea navioides is relatively common in the nursery trade, the prolific and compact S. rafaeli is becoming more readily available from bromeliad specialty nurseries.
Sincoraea is a generic name resurrected for these species from a taxon Ernst Ule used for his 1908 description of S. amoenum. While the name change is somewhat controversial among some old school bromeliad growers, I happen to agree wholeheartedly with this decision since these plants never seemed a good “fit” for Orthophytum to me.
In coastal north-central California I have found that a surprising number of species are temperature tolerant to withstand brief overnight lows to -2.20 degrees C (28 F) and brief daytime highs of ~38 degrees (~100 F). Of five species trialed that were left fully exposed to the sky on concrete decks for several winters running, only fully-exposed S. navioides and S. burle-marxii var. “seabrae” consistently died following prolonged exposure to cold and rain this past winter. Duplicates of these same plants grown outdoors under the same conditions but with some overhead protection did show some light brown tipping of the leaves, but otherwise survived visibly unscathed. I am referring here to flowering-sized plants and their attached offsets. Recently-separated offsets and seedlings should be provided with minimum temperatures of 5 degrees C (~40 degrees F) and slightly drier conditions than well-established plants. The most cold-wet tolerant species that I cultivate is S. sp. “Bahia” from Tropiflora, which is very much like some S. burle-marxii variants, and the spectacular bigeneric hybrid xSincoregelia ‘Galactic Warrior’ (formerly xNeophytum). Relative hardiness aside, I doubt they could handle any sort of lengthy freeze anywhere.
I grow all of mine in terracotta bowls of various sizes and 15 cm (6”) plastic azalea pots in a medium with very sharp drainage, consisting of (by volume) ~50% pumice, ~40% fine conifer bark and ~10% milled peat with a bit of red lava chips. This mix is pH amended to a slightly acid reading and fertilized with nutricote 14-14-14+ micros. A number of other successful growers use a greater percentage of fine bark as a major component of their growing mix, so there is room for experimentation as long as it is very free-draining. Plants achieve their best color at moderate temperatures with near full sun exposure all day. They require frequent watering when grown hard but are somewhat drought tolerant if shielded from intense sunshine. Under my current conditions, I try not to let the media dry out completely between waterings. In spite of living in an area with very bright sunshine for much of the year, the plants in the Bay Area rarely achieve the color intensity of these same plants grown fully exposed on my deck in Guatemala at ~5,000’/1,550 m, presumably due to greater UV intensity and 11-13 hours of full sun exposure. I have found them to be generally good subjects for growers with very bright bay windows, although they do grow rather larger than the norm like this and the colors are quite a bit less intense at anthesis. Plants I have grown on a bench in a cool, shaded greenhouse in California are etiolated and rather uninspiring when in flower, so long periods daily of very bright light is almost a must to see them at their best. Photos of these plants taken in situ in Brazil and posted on the internet usually provide a good template of what to strive for in cultivation.
While not as hardy as other landscape suitable rosetted “spineys” like Hechtia spp., Ochagavia spp. and Fascicularia bicolor, they are far more manageable than those genera for pot culture and are quite a bit less hard on bare hands and arms. They are also, in my opinion, infinitely more striking than the average Dyckia, especially when flowering. Pretty much pest-free, but keep an eye out for mealies in the leaf axils. Most are 14-18"/35-45 cm across when mature.
In full color, they are outstanding in mixed, massed plantings. I am not sure how well these plants would do in areas with extended periods of daytime temps over 95 F/35 C, warm nights and low RH (e.g. southern Arizona and parts of southern California), but my collection has been exposed for short periods of time to daytime highs of ~100 F/=>38 C coupled with fairly low RH on quite a few occasions over the past three years with no visible damage to the plants. Plants grow in warm, humid greenhouses and/or shadehouses in Florida do surprisingly well, but their colors are quite a bit less intense than one would consider optimum.
Sincoraeas are great companion plants for fantasy aloes and showy, dwarf cacti on a patio table.
I have attached images of a number of my plants in flower. Missing is one, perhaps the most beautiful of all, that hasn't bloomed yet (the amazing S. heleniceae) but is finally offsetting so should do something soon.