Jennifer Schultz Nelson
Extension Educator, Horticulture
The weather this time of year is challenging whether you consider yourself a gardener or not. After a long cold winter, we're ready for spring.
Personally, I dislike the month of March more than the cold snowy days of January. At least white snow is brighter than the muddy brown landscape that is revealed once the snow melts by March. Dreary brown rainy days of March make me feel like Spring will never come.
Some home gardeners brighten their homes with flowering houseplants to chase away the gloom of a long winter. African violets are an old standby, but have you heard of the African violet's cousin, Streptocarpus?
Like African violets, Streptocarpus are also native to Africa. Streptocarpus are native to southern Africa and the island of Madagascar. The name Streptocarpus means "twisted fruit" in reference to the shape of this plant's fruit.
One common name for Streptocarpus is Cape Primrose, referring to the plant's resemblance to the genus Primula. There are about 155 recognized species of Streptocarpus. The first species described was S. rexii, which was the basis of many of the first cultivars intended for indoor and outdoor cultivation. Today many cultivars are based on crosses of different Streptocarpus species.
Streptocarpus have very textured, oblong, leather-like leaves. Judging by the leaves, they don't look much like African violets. The flowers on the other hand, hint at their relatedness.
Flowers are trumpet shaped and borne on leafless stalks held above the foliage. The shape of the petals is very reminiscent of an African violet. Colors of Streptocarpus are similar to African violets-- many shades of violet, blue, pink, and white. Unlike African violets though, there are true red cultivars of Streptocarpus, such as the cultivar 'Midnight Flame' with very attractive deep red blooms.
Modern breeding efforts have resulted in a multitude of different color combinations within flowers, as well as plants which flower for nearly the entire year. Breeders have also worked to take the few Streptocarpus species with scented flowers and cross this trait into new hybrids. 'Bristol's Sally Mander' and 'Bristol's Goose Egg' are examples of modern hybrids with scented flowers.
Care of Streptocarpus is much like that of its cousin the African violet. Bright indirect light is best. An east or west facing window is ideal. A southern window may be too bright for at least the summer months. Use a sheer curtain to moderate the light's intensity if this situation occurs.
Streptocarpus prefer moderate to cool home temperatures, just like most people do. Day temperatures of 50 to 70 degrees Fahrenheit and night temperatures of 45 to 65 degrees Fahrenheit are perfect for this plant.
One of the big places that a person can have trouble growing this plant, like many plants, is watering. Overwatering is a sure-fire way to kill a Streptocarpus. Growers advise that use of a very light, well-drained potting mix helps to reduce problems with too much moisture.
Propagating Streptocarpus is done by either division, as the plant grows from multiple crowns, or growing points, or by leaf cuttings. To make leaf cuttings, take one leaf, remove the large central vein, and place the two remaining halves "center" edge down in growing media, like two slices of toast in a toaster. Plantlets should form in a short time along each leaf edge. It would not be unusual to have one two inch section of leaf produce 20 to 60 plantlets.
Many Streptocarpus fans consider this plant to be a lot hardier and "harder to kill" than its cousin the African violet. I myself have successfully killed the two plants I attempted to grow. But I know now that I killed them with too much water. I will try again, in line with a saying I've heard that "you haven't really failed at growing a plant until you've killed it at least three times".