by Bruce Brethauer
I always like to keep a lookout for interesting succulents from plant families which are not usually associated with the succulents. Even so, about three years ago, when Bill Hendricks, president of the Midwest Cactus and Succulent Society, offered me a plant of this species, I was a little skeptical; he told me it was a Gesneriad, the same family from which we get African Violets, Streptocarpus (the Cape Primrose), Achimenes and the plant which many of us once knew as Gloxinia. Over the years, I had grown, or attempted to grow, each of these without great success - a few plants did well enough for a few years, but none thrived under the conditions which I was able to provide, so I initially thought it best to decline Bill’s offer, but he pressed the issue, saying "Grow it for a while and see what you think of it." - I could hardly decline. After several years of growing this plant, I can report that it is a surprisingly tough plant, which has tolerated many weeks (and sometimes months) of neglect, and growing conditions which have ranged from scorching heat, to nearly freezing; full exposure to sun, to partial shade, months of drought, and periods of frequent heavy rains. Through it all, it has persisted, slowly growing a low caudex-like hard tuber, and a canopy of attractive, felted leaves, held some 4 to 6 inches above the soil on my plant.
The stems and leaves are covered with soft white hairs; new growth sports a particularly dense "fur" giving them a soft, silvery appearance, reminiscent of "pussy toes" and "wooly lamb’s ears". The leaves and stems, while ultimately deciduous, are quite durable and long lived, in my experience, persisting for one, and sometimes to nearly two years before being shed. New stems and leaves are usually produced before the old ones are completely shed - so that this plant may never become entirely leafless as can be the case with some other caudiciforms. The leaves and stems of this plant are not adapted for water storage, so it may not have an immediate appeal to growers who are looking for plants which are more obviously succulent. On the other hand, it should appeal to growers who are looking for an easy, drought tolerant plant which does not produce spines and irritating sap. But this is a succulent plant, which produces a very large tuberous root which can eventually grow to massive proportions, reputedly growing to a diameter of 12 inches in very old plants. The tuber typically grows at the surface of the soil, with its upper portions exposed - roughly similar in appearance to the caudex of brachystelma. The tuber grows very slowly over time - taking several years to grow to a size of about 2 inches across. As the tuber becomes lager, plants typically produce multiple stems and many leaves, so that very old plants can produce quite a canopy of leaves.
The flowers, while small, are a bright orange/crimson color, contrasting dramatically with the fuzzy, silvery white leaves. The flowers are long and tubular, and are said to be pollinated by hummingbirds in habitat, suggesting that they are also rich in nectar. The flowers are self fertile, and can easily be pollinated by inserting a fine artists brush into their tubular flowers. After pollination, seed capsules develop, eventually releasing their tiny seed.
The plants can be propagated by dividing the occasional root offset, or by seed. Bill Hendricks is the only person I know to have propagated this plant from seed. He assures me that it is not difficult to grow, but like all gesneriads, the seed are tiny - practically dust-like threads, and may require some special handling. Bill uses Metro Mix, but any good seed starter potting medium would probably work well. On top of this, put down a very thin layer of sifted sand (use the coarse sand left after sifting off the finer particles), or Turface All Sport. On top of this sew the seed, and use a mister with a mix of Captain solution to moisten the soil, and to prevent any fungal growth in the potting mix. Following this, the pot should be sealed in a plastic baggie to maintain moisture and high humidity. The seed trays should be maintained at relatively warm temperatures (about 70 to 78 degrees Fahrenheit) and given bright, filtered light about 10 to 14 hours daily. Many growers use banks of fluorescent lights to provide illumination for germinating seeds and raising seedlings; held several inches above the seed flats, these not only provide adequate light, but also additional warmth. Bill reports that germination is fairly rapid, but subsequent growth may proceed a bit more slowly - many caudiciforms and tuberous rooted plants will invest most of their initial growth to develop their roots/caudexes. Bill tells me that using this technique, he has been able to leave the seedlings in the sealed baggie for over a year - the initial application of Captain can effectively prevent fungal growth so long as the seal on the baggies are not broken. When the seedlings have grown large enough to be safely transplanted, they should be potted individually. Thereafter, it is a rather long process for the plants to grow their distinctive caudex.
This species is native to Brazil, and has been given the name "Brazilian Edelweiss", suggesting that it also grows at higher elevations under more or less alpine conditions. It was once classified as Rechesteineria leucotricha, but in more recent years, this and several other genera have become consolidated into the genus Sinningia, which is characterized by tuberous rooted species.
This is an easy, undemanding plant, tolerating a wide range growing conditions; while I have found it responds well to my basic succulent growing suggestions, I suspect that it would probably grow better with slightly more frequent watering and fertilization during its growing season. It is a good plant for those growers who prefer succulents without spines, or toxic sap, and for these same reasons is well suited for households with young children, and inquisitive pets. The soft leaves are very tactile, and are suitable for growers who like to touch their plants, and may be of particular interest to younger growers. Sadly, this is not an easy plant to find in the trade - few mail order nurseries specializing in succulent plants will carry this species, it may be easier to acquire a plant through an African Violet Society, as many members will likely grow additional species from the greater gesneriad family. This plant may not have quite enough character to satisfy the hard core growers of other caudiciform plants, but its attractive foliage and flowers will endear it to other growers. If you ever manage to come across a plant for sale, I can only repeat the advice of Bill Hendricks, "Grow it for a while, and see what you think of it."