A Botanist’s Guide to the African Violet

The African violet is one of the most popular houseplants due to its wide availability, low price, ease of growing indoors, and year round colorful flowers. Although African violets can be found even in grocery stores, they are actually quite exotic with a rich history. It is easy to provide the right environment to make African violets thrive and bloom indoors once the plant’s growing needs are learned. There are so many different cultivars of the plant that there is sure to be an African violet to suit the tastes of any person.

History and Taxonomy

African violets were discovered in 1892 by Baron Walter von Saint Paul, who was the governor of the German colonies in East Africa. The story goes that the Baron was walking with his bride to be on his plantation near Tanga, Tanzania in 1892 when he spotted the African violet flowers growing near a stream. He picked a bouquet for his fiancée and later ended up sending seeds to his father back in Germany. His father had a great interest in botany and soon the plants became popular in Europe. Herman Wendlean, a famous German botanist at the Royal Botanical gardens, gave the plant the genus name of Saintpaulia in honor of Baron Walter von Saint Paul, who discovered it. The species name ionantha means “with flowers like a violet” in Latin. It is important to note, however, that the African violet is not a violet at all; in fact, it is not even remotely related to true violets. Growing African violets skyrocketed in popularity in the 1930’s with the introduction of hybrid varieties and the invention of fluorescent lighting, which allowed the plants to bloom year round.

Plant Description

The scientific classification for the common African violet is as follows:

  • Kingdom: Plantae
  • Phylum: Trachaeophyta
  • Class: Angiospermae
  • Order: Scrophulariales
  • Family: Gesneriaceae
  • Genus: Saintpaulia
  • Species: ionantha

However, there are approximately 8 other species, 9 subspecies, and hundreds of cultivars. Classifications have changed over time; previously there were thought to be 20 different species which have been narrowed into 9 since 2009. African violets come in a variety of colors from white to nearly every shade of violet, pink, and purple a person can imagine, and even blue; flower forms can be double, star shaped, ruffled, fringed, and more. Although some flowers are a pinkish red, true red and true yellow are yet to be produced. Flowers can also be bicolored, multicolored, and spotted with specific markings. Leaves range from light to dark green or even variegated. The leaves come in a variety of different forms as well, some of which are plain, ruffled, quilted, and scalloped. Miniature African violets are 6 inches or less, semi-miniatures are 6 to 8 inches, standards are 8 to 16 inches, and large are over 16 inches. New cultivars are always being developed-improved vigor, disease resistance and different varieties of flowers and sizes are always being sought. Miniatures and trailing violets are very popular right now.

Lighting

One of the reasons that African violets do so well indoors is that in their natural environment, they are found in shade. Light intensity and duration are the most important elements in getting African violets to flower. African violets do well very near to a North or East window in the summers or to a South or West window in the winters. Plants that receive too much light exhibit pale, yellow green bleached out leaves, short leaf stems, and even burned brown areas on the leaves. Plants that don’t get enough light have thin, dark green leaves, long petioles and will rarely flower. African violets do very well under fluorescent lighting as well. There are many variations in the fluorescent lighting methods that growers use, but the consensus of growers agree that providing 600 to 900 lumens of lighting at an average of 16 hours a day is best. To do this, two 40 watt wide spectrum fluorescent bulbs should be placed approximately 12 inches above the plants. If you plan to have these plants in your garden, you would likely be better off having a sun-absorbing patio umbrella to offer at least partial shade.

Temperature

African violets respond best to a night temperature of 65-70 degrees and a daytime temperature that is 10-15 degrees higher. If the temperature gets below 60 degrees, leaves may become deformed, discolored, and brittle; flowers and buds may drop and turn brittle. If growing African violets on the windowsill in winter, slide a piece of cardboard between the glass and the plants to prevent them from getting too cold, or move them off of the ledge. Plants that get too cold will have darkened leaves that become mushy and wither. Leaves touching a cold window pane may become damaged or die. At temperatures above 80 degrees, growth and flowering of plants will stop or slow. Remember that as the temperature changes, light may have to be adjusted or vice versa.

Humidity

African violets love humidity, but as the temperature changes, so do their humidity requirements. Generally the plants need 50%-70% humidity but they may need more in summer when temperatures are high and light is intense. In winter, they need less humidity; too much can cause root and leaf rot. In the home, potted plants can be placed on humidity trays, which are shallow plastic trays filled with gravel and filled slightly with water; however, the bottoms of the pots should not be sitting directly in water. The water will evaporate off the stones and supply humidity.

Media and Potting

In nature, African violets are found growing in shallow rock crevices. They have very fine roots and need an airy, well drained planting medium rich in organic matter to mimic their natural growing habit. There are many commercial mixes available just for African violets, or mixes can be made at home from combining peat moss, vermiculite, and perlite. Containers should have drainage holes, but they can be placed inside of decorative pots if desired. If the pot does not have drainage holes, the plants have to be watered very carefully to prevent overwatering. Plastic or terra cotta pots may be used, but pots should be no deeper than 4 inches since African violets have shallow roots. Choose a pot diameter the same size as the roots, which are usually 1/3 the size of the leaf crown. If the pot is too big, the roots will not be able to absorb all of the water in the pot and the roots may rot.

Fertilizing

African violets thrive on a consistent feeding schedule. Liquid fertilizers are generally the best method of feeding. There are many commercial fertilizers specifically for African violets. A good fertilizer for this plant should be low in ammonia, urea, and salts and high in nitrates. 15-16-17 peat lite special, 14-12-14, and 15-15-15 are all appropriate fertilizer combinations for African violets. Newly potted plants should not receive fertilizer until they become established. Fertilizer is only needed when the plant is actively growing, so often in wintertime, windowsill plants do not need it. If growing under lights, then it is needed year round. Be consistent and don’t forget to feed for regular and prolific flowering.

Watering

There are various opinions on the best way to water African violets. Watering from the top should be done in the early morning so that the leaves dry quickly. However, if the water is colder or hotter than the room temperature, unsightly circles appear on the leaves; this is called ring spot. For this reason, many growers prefer to water from the bottom by filling a saucer with water and sitting the pot in it. Let the pot stand until the soil is moist then dump out the rest of the water. Occasionally, the plants will need to be watered from the top with room temperature water to leach out salts that have accumulated. Wait until the top inch of soil feels dry before watering again. Plants that are over-watered will rot, and plants that are under-watered to the point of wilting are stunted and often never recover.

To see African violets in their native habitats, you would have to visit the exotic coastal forests of Kenya and Tanzania. Sadly, although hybrids of the original species can be found neglected in any home or grocery store, they are very rare in the wild and are fast disappearing. Given the exotic history and stunning beauty of this little plant, it is amazing that it is available for such a small price at stores all over the world.