The genus streptocarpus, which is commonly known as the Cape primrose, has about 150 species. It is characterized by its spiral fruit, which gives it the name streptocarpus, meaning twisted fruit. Belonging to the Gesneriaceae family, its flowers are flared, trumpet-shaped and come in a wide variety of color shades, including blue, pink and mauve, and have striped markings. Streptocarpus is an herbaceous flowering plant that flowers all year and is native to places such as Africa and Madagascar.
The Cape primrose is a perennial that grows to a height of 12 to 18 inches (about 30 to 45 centimeters). They typically need bright indirect light and can be ideal windowsill plants. Though they are not considered delicate, they cannot withstand long exposures to direct sunlight. Long exposures can result in burned leaves — usually three to five hours of morning sunlight is tolerable. The minimum temperature requirement for these flowering plants is about 51 degrees Fahrenheit (15 degrees Celsius), but they prefer moderate temperatures of about 65 to 80 degrees Fahrenheit (18 to 27 degrees Celsius).
A cousin to the African violet, the Cape primrose is a prolific flower producer — one plant can successively produce six to ten stalks from every leaf. For every leaf that grows, an accompanying growth of flowers blooms. Hybrids have been produced featuring Cape primrose flowers that are red and some that are scented as well.
It can be fairly easy to grow streptocarpus, as they can be grown from seeds, leaf cuttings and divisions. Their tiny, dust-like seeds can be scattered on the soil surface and exposed to indirect light in order to germinate quickly. Some species can be propagated from stem cuttings, while others can be split by cutting the leaves into sections or down the middle to be replanted. Having a preference for lightly draining soil, they can grow in any place where seed can germinate.
The Cape primrose should be watered with care, as over watering can easily cause root rot. Watering can be done once a week during the winter and twice a week during summer if they are grown in potting soil where the conditions can be regulated. It is best to use water that has been purified and stripped of chemicals in order to produce the best flowering and plant growth.