Streptocarpella: The Houseplant That Flowers All Year

Because it is easy to grow and flowers most of the year, the Streptocarpella makes an ideal gift, and that is how this plant entered my life.  Its fuzzy, chubby stems and leaves were not particularly impressive, but its flowers are a heart-stopping lavender blue that will enliven any winter day.  But there’s more — as I discovered when I moved my streptocarpella out onto the deck for the summer.  Its stems cascaded over the sides of the pot and it bloomed profusely all summer long.  And though there are recommended cultural practices, basically this plant will perform beautifully even if you don’t provide ideal conditions.  The only problem I’ve had is figuring out its proper name.  My friend gave me only one name — streptocarpella — and she explained that to remember it, just think of strep throat.  Ugh.  The official pronunciation is “strep-toe-CAR-pell-uh” — but there’s nothing about this plant that will remind you of strep throat; it’s easy to grow, adaptable, and is simply gorgeous all year.

Names and Confusions

Streptocarpella is a tropical perennial found in moist, warm, and humid forests of Africa and is part of the large Gesneriaceae family, known as the Gesneriads (pronounced either “guess-NARE-ee-ad” or “jez-NARE-ee-ad”), which includes African violets and the well-known Cape primroses.  After a bit of research, I discovered that my plant is part of the large Streptocarpus genus of evergreen perennials, monocarps and annuals which can be grouped into three very different growth forms:

–stemless clump-forming rosettes (the “rosulates”), including Cape primroses

–unifoliates (plants with a single leaf)

–soft, shrubby-stemmed plants

Streptocarpella is in the third group; it has stems (“caulescent”) and a more typical plant structure.  It’s probably no surprise that streptocarpella is often confused with its relatives in the first group, which are usually referred to as Streptocarpus, even though these two “strepts” are markedly different in form.   Because these two groups of plants are closely related, they are each classified as a subgenus of the genus Streptocarpus.  So those one-leaf wonders and the Cape primroses are properly called — get ready, it’s a mouthful — Streptocarpus subgenus streptocarpus, while my gorgeous houseplant is properly identified as Streptocarpus subgenus Streptocarpella.  There’s probably no need to master this mouthful, as many reliable authorities will refer to this plant as Streptocarpella saxorum, or Streptocarpus streptocarpella or simply as streptocarpella, which seems to function as a sort of common name.  The plant does have a few common names.  I have seen it referred to as nodding violet, false violet, Cape violet and even, oddly enough,  “Cape primrose.”

It’s worth noting — especially for those with an interest in plant classifications — that in recent years taxonomists have re-classified the Streptocarpus genus and placed African violets in the Streptocarpella subgenus.   If you’d like to know more about the taxonomy and reclassification, especially as it affected African violets, you’ll want to read articles on the rather extensive Gesneriad Reference Web, including, gesneriads.genera/streptocarpella and gesneriads.genera/Streptocarpus Saintpaulia.

And if you’d like to see photos of the many unusual plants in the Gesneriad family, you’ll enjoy the page entitled “Gesneriad Genera,” at Gesneriad Reference Web/Genera.  It was a real eye-opener to me, and it helped me understand why this family of plants is so popular with plant hobbyists and is the focus of conventions and shows.  www.gesneriadsociety.org.

 

Species and Hybrids

Most of the species in the subgenus Streptocarpella are not in cultivation, though a few are widely available in Africa, Europe, and North America as house plants and tender garden plants, including S. caulescens, S. kirkii, S. saxorum, S. glandulosissimus and S. hilsenbergii.  There are a few hybrids, but the best-known and most commonly available one is S. ‘Concord Blue’ — pictured at right.

Now that I’ve warned you of all the possible name confusions, let me set your mind to rest with these wise words from plant guru Allan Armitage:

“Species that are useful for summer baskets and containers are similar in appearance, with small ovate leaves and 1-1½” long lavender tubular flowers.  They may be Streptocarpus glandulosissimus, S. orientalis, or S. saxorum, but it is difficult to know just what is being sold out there.  Quite truthfully, this really doesn’t matter: given low light and consistent moisture, plants are full of flowers throughout the summer into the fall.  . . . Whatever is bought under the name Streptocarpus or Streptocarpella will enjoy filtered light and moist, but not wet, soils.”

— Armitage’s Manual of Annuals, Biennials, and Half-Hardy Perennials (p.456)

 

Growing Streptocarpella

Streptocarpella is hardy in Zones 9 and 10, and it’s usually grown as a house plant in North America.  Plant it in well-drained organic potting mix in a container that allows room below for the cascading stems — a plant stand is ideal.  Place it in an area of bright light, but not direct sun.  Windows that face either south or east are recommended.  My plant is very happy in a south-facing window which is somewhat sheltered from direct sun.   Water it regularly, and avoid getting water on the leaves because it causes browning.  You’ll notice that the blooms appear on wiry “scapes” that are produced at the stem nodes.  I’ve never pruned these after blooming, and my research suggests that no pruning is necessary.  I DO need to repot my plant, which is getting potbound, but that’s an exciting prospect since by dividing it, I’ll gain a new one.

In late spring — after all danger of frost is past — I move my streptocarpella onto my deck into a position where it gets a bit of protection from hot afternoon sun.  Sometimes I place it on a table, where its stems will cascade almost to the floor, but you could try putting it in a hanging basket, a very popular alternative.

For a photo of a lovely container garden featuring streptocarpella along with a number of other plants, see AggieHorticulture/Container Gardens/Tex.A&Am.

Propagation

Streptocarpella is reportedly easy to propagate, especially from stem cuttings.  Cuttings of about 2 to 4 inches can be taken beneath a leaf node. When the cutting is placed in clean water, it will sprout roots. Keep the cuttings in bright, indirect light at about 65-68°F. Once the roots are about 2 inches long, you can pot up the cutting.  For a photo showing a cutting in a small water glass, check out womanswork.com/2013/03/22/my-favorite-houseplant-streptocarpella-saxorum.  Directions for growing from seed are available at PlantZAfrica/Streptocarpus saxorum.

If you are enamored with the idea of a houseplant that’s an unfussy non-stop bloomer, you’ll want to try streptocarpella. My local nursery just recently assured me that they’ll be arriving soon.

 

 

 

SOURCES:

Armitage’s Manual of Annuals, Biennials, and Half-Hardy Perennials (2001), p. 456.

“Streptocarpus subgenus Streptocarpella,” The Gesneriad Reference Web/genera/streptocarpella/

“Global Plants” database at https://plants.jstor.org/compilation/streptocarpus.glandulosissimus (Note: Global Plants is the world’s largest database of digitized plant specimens; its search page is at https://plants.jstor.org.

“Plant of the Week: Streptocarpella,” Univ.Ark. Ext. Resource Library

“Streptocarpus saxorum,” PlantZAfrica,  South African National Biodiversity Institute

Gesneriad Reference Web: Growth Forms

Feature photo courtesy of Fairview Gardens, Raleigh, North Carolina