History and interesting facts about African violets

As their name suggests, African violets are native to the coastal mountains and rainforests of east African countries such as Tanzania and Kenya, where temperatures vary from around 18 to 32°C, and the average annual humidity is 77%. They are low-growing plants of the forest floor where they can often be found growing between rocks in small pockets of soil, where they receive dappled sunlight and are protected from harsh light by the canopy of trees above.

Baron von Saint Paul, who was serving as the Imperial District Governor of Tanginyika, a small country in east Africa, discovered and collected two of the plants we now call “African violets” in 1892 and sent seeds to his father in Germany. His father was impressed with their delicate beauty, and took them to Hermann Wendland, botanist and Director of the Royal Gardens of Herrenhausen in Hanover.

It was Wendland who gave the plants their botanical name (Saintpaulia ionantha). The genus name Saintpaulia was named after the Baron and the species name ionantha means “resembling a violet” in Greek. However, despite their common name, African violets are not a type of violet, and are now categorized in the genus Streptocarpus.

Because of their exotic looks African violets became popular pot plants and were introduced to the United States by a New York florist in 1894. But in the drafty homes of the late-eighteenth-century, the plants often took a chill and died, earning the plants the reputation of being finicky and difficult to grow.

It is probably not a coincidence that the popularity of African violets increased with the introduction of the fluorescent light bulb in 1938. Gardeners soon realised the ability of African violets to bloom almost continuously under such conditions, and this, along with their wide variety of flower colours and foliage, created a whole new trend of gardening under lights.

African violets became so popular that in 1946, only 8 years after the introduction of the fluorescent light bulb, the first national African violet show was held in Atlanta, Georgia. The show was so popular that Atlanta police were called in to control the crowds and traffic!

The African violet quickly spread worldwide and is one of those plants that never go out of fashion because it is simply irresistible, and today African Violet Societies and Clubs can be found in all major cities of the world.

Modern African Violet Varieties & Hybrids:

Once found only in the coastal woods of east Africa, African violets are now among the most popular flowering houseplants. Hundreds of varieties and hybrids exist, from tiny miniatures to beautiful trailing varieties!

Flower colour varies from blue to violet, lavender, pink, red-violet, blue-violet, lavender-pink and white. Flowers may be single, double, semi-double, star-shaped, fringed or ruffled. Some varieties produce flowers with two or more rows of petals of one colour with the rest fringed in a different colour. Leaf types are described as plain, quilted, spidered, ruffled, fringed, scalloped, spooned, pointed and variegated, and their colours range from dark to bright green, silvery green, or variegated, and may be round, oval, or heart-shaped, and usually have a velvety texture.

African violets are typically classified by size, based on how wide they grow:

Miniatures grow less than 20cm across

Standard types grow 20 to 40cm across

Large types grow more than 40cm across

Many modern African violets are the result of the hybridization of two species. Most often the parent plants are Saintpaulia ionantha and Saintpaulia confuse, resulting in the rainbow of flower colours and beautiful foliage types and sizes gardeners enjoy today.  

How to care for African violets indoors

Knowing the climatic conditions they grow under in their native habitat will go a long way in understanding how to treat them in our homes. And because they are quite tolerant of conditions outside of their ideal range, if you follow a few simple care rules they will flourish.

How much light do African violets require indoors?

Being understory rainforest plants in the wild, African Violets don't need direct sun, but if you want blooms repeatedly throughout the year, lighting is most important. Indoors they require bright but indirect light for 12 hours per day. A north or east-facing window is best, but to avoid the risk of burning their sensitive foliage, keep them at least 60 to 90cm away from very bright north facing windows. If you have an African violet with variegated leaves, too much light and heat can reduce variegation and turn the leaves fully green.

If lighting is not adequate, artificial lighting like fluorescent or LED lights work well to supplement natural lighting. When using a grow light, give your plants at least 6 hours and ideally up to 12 hours of good light a day. If they only receive natural bright light for 6 hours, supplement with a grow light for the other 6 hours.

Thin, dark green leaves on leggy stems indicate that the plant is getting too little light, and on the other hand, light green or bleached leaves indicate too much light.

Give your plant a quarter turn every week or two, otherwise they tend to bend towards the light and also grow bigger leaves on the side that gets more light, ending up lopsided or falling over.

What is the optimal temperature for growing African violets indoors?

African violets grow best and produce the most blooms in a warm position. Temperatures should not drop lower than 13°C at night, and the plants must be kept away from drafts in winter. During the day the ideal growing temperature is 22°C, and should not exceed 27°C.  Basically, if you are comfortable in a room your African violet will also be.

How much humidity do African violets require indoors?

Although African Violets are quite obliging indoors, in very dry regions you want to maintain a healthy humidity indoors. Humidity levels between 40 to 60% are ideal.  Cheap hygrometers are available to help you keep an eye on humidity levels, and installing a home humidifier would be ideal.

What growing medium do African violets need?

African violets thrive in slightly acidic to neutral soils that are well-drained but are still able to retain moisture. Keep your plant consistently moist but not soggy. Special potting mixes for African violets would be best to use, but if you can’t find it can also make your own growing medium.

If you search ‘DIY African violet potting mix’ you will find a lot of different 'recipes', but most will contain peat, perlite and vermiculite. Because peat moss is no longer considered sustainable and many countries have banned its extraction, palm peat is used as a substitute. Various ratios are used: 50% palm peat, 25% perlite and 25% vermiculite; or 3 parts palm peat to 2 parts perlite and 1 part vermiculite; or one third palm peat and one third each of perlite and vermiculite.  

How to water African violets?

In their natural rainforest habitat, African violets seldom fully dry out, and in the home they can be a little bit finicky about watering, so be careful not to overwater, as the soft stems are very susceptible to rot. African Violets prefer to stay evenly moist at all times, but never water-logged or soggy.

The first sign you need to water is when the top few centimetres of growing medium is dry. If your plant's pot isn't too full of foliage, you can stick a finger into the soil to check if the medium is dry, otherwise a slim water meter designed for smaller, shallower pots is a great way to check without breaking the fragile stems of the plant.

When in bud and flower, African violets become even less tolerant of drying out which can cause buds to abort flowering, and flowers to brown and die early.

Do not get African violet leaves wet

When watering it is recommended that you do not get their leaves wet. This seems to be a contradiction in terms, as we know that their native habitat is the humid, sometimes very wet rainforests, where of course their leaves get wet? Wet leaves are not the problem, it’s when they stay wet for too long that's the problem, and outdoors the leaves dry out much quicker than those growing indoors, making the plants susceptible to rot. Also, contact with cold water, especially in winter, can be very damaging to the leaves.

Water sitting in the crown of the plant can quickly lead to stem or crown rot, a common problem caused by the fungus Pythium or Phytophthora which can attack the roots and crown of African violets. It tends to spread fast and most often results in the death of the plant. Wet leaves can also develop botrytis or mildew.

To get around this issue, you can use watering wicks in your pots or water from below by allowing the plants to stand in drip trays filled with room temperature water. Let your plant have a good long soak until the top of the substrate is wet to the touch. Don't leave your African violet sitting in a saucer full of water all the time though, as this can cause rot. If you use a watering can with a thin spout you can avoid getting the leaves too wet, and if they do get wet you can pat them dry with a paper kitchen towel.

Is tap water safe for African violets?

Generally, tap water is fine for African violets but there are some exceptions, including water that's been softened (normally with sodium chloride), water high in chlorine or chloramine, or water with a pH outside their preferred range of 6.5 to 7.5. If your tap water is not suitable clean rainwater or filtered bottled water is a great alternative.  

How to clean African violet leaves

The fuzzy leaves have a tendency to collect dust and dirt which can be gently dusted off using a soft-bristled brush. Those big makeup brushes are great.

Provided the leaves can dry out quickly the plants can be taken outdoors occasionally to a shady spot in the garden, and hosed down gently to refresh the foliage.

How to fertilise African violets

Because African Violets flower repeatedly, they require feeding during their active growing season in spring and summer. However, over-fertilising is a more common problem than under-fertilising, and many potting mixes already include nutrients, so your newly purchased little plant may not need feeding for a while. For this reason many gardeners only start to fertilise new plants when the plant appears to need an extra boost by showing slower, thinner growth and pale or yellowing leaves.

Thereafter, feed regularly with a specialist African violet fertiliser or any balanced liquid fertiliser for flowering plants.

Leaching the soil of African violets

It is natural for mineral salts from your water and your fertiliser to build up slowly over time, changing the pH of the growing medium and causing some nutrients to become toxic and others to be locked out, resulting in deficiencies. The excess salts can also damage roots and increase the risk of root rot and fertiliser burn.

For this reason, some growers recommend top watering every month or so. To leach out the excess salts, water your African violet from the top quite heavily so the water pours out from the drainage holes. Another way to avoid a build-up of salts is to repot at least once a year into fresh growing medium.

When to transplant African violets

In the wild African violets grow in small pockets of soil so they love to grow in small pots, and this also encourages them to bloom. A sure sign that they need to be transplanted into a slightly bigger pot are leaves that wilt very quickly after watering. When repotting, do not use a pot that is too big - As a general rule the pot should be no more than one-third the width of the foliage. Do not plant African violets too deep.

Pruning African violets

All you need to do to prune your African violet is remove the outer ring of older leaves as they fade or turn brown. You can also snip off flowers as they fade.

African violet propagation

African violets are easy to propagate by leaf cuttings. Trim off a healthy, mature leaf with about 2.5cm of stem. Place the cut stem into a good soilless rooting mix like palm peat, planting deep enough that part of the leaf is touching the mix. This is where new leaves will form. Once you have four to six leaflets, you can remove them from the mother flower and pot them. Leaves will also root if placed in a glass of water.

The most trouble-free method of propagating violets is to make a greenhouse using clear plastic food packaging boxes. Fill the bottom of the box with 10cm of moist palm peat and then plant overlapping violet leaves into the soil. Put the clear plastic lid on top and tape it closed. Place the sealed box in a warm place with bright light, and young violet plants will appear within 8 to 10 weeks and be ready for transplanting in three months.

Problems, Pests & Diseases:

Why is my African violet not flowering?

The number one reason an African violet refuses to flower is insufficient light. Shift your plant to a brighter spot, or if you don't have somewhere suitable, consider a grow light.

Another reason for no flowers may be not feeding at all, or using the wrong fertiliser. Feed regularly with a specialist African violet fertiliser or any good liquid fertiliser for flowering plants. 

Calcium deficiency can cause small or deformed leaf growth, and bud blast, where buds form but fail to open, going brown and dying prematurely. If you are not using a specialist fertiliser for African violets, check the label of your fertiliser to ensure that it does contain calcium, as not all fertilisers include calcium.

Low humidity can also cause buds to form but fail to flower. Dry air and being in the path of drafts can both be to blame.

Another reason for no flowers is your pot is too big, or on the other hand, not flowering when everything's ideal can also signal it's time to repot.

Cyclamen mites

Cyclamen Mites (Steneotarsonemus pallidus) are not insects but are more closely related to spiders. They are one of the most serious pests of African violets because they are extremely small and cannot be seen with the naked eye, so typically damage to plants is the first indication of their presence.

Cyclamen mites develop most rapidly when the humidity is high humidity (80 to 90 percent) and the temperatures are cool, at or near 15°C. They feed on the sap of new growth in the centre of the plant, and during feeding they inject a toxic chemical that disrupts normal growth patterns.

Symptoms may include severe stunting of leaves in the centre of the plant, sometimes with leaf curling. New leaves are often very hairy, making them greyish in colour. Flower buds may also be stunted and misshapen or even fail to open.If ignored, the entire plant may die. Even after infestations are controlled, some symptoms will remain. A return to a normal appearance requires time and a gradual pruning of distorted leaves.

Prevention & Control:

Space plants so that they do not touch to prevent the spread of cyclamen mites. Isolate infested plants, and also be careful not to touch infested plants before working with non-infested plants.

Badly infested plants should be discarded, and their pots should not be reused until they have been thoroughly scrubbed clean and then soaked for 30 minutes in a solution of 1 part household bleach to 9 parts water.

The African Violet Society of America recommends Neem Oil as an insecticide and miticide for African Violets, including Cyclamen Mites. Insecticidal soaps also work well as gentle insecticides.

Take the plant outside during mild temperatures and spray.  Two or three sprays at three-day intervals may be required for mite control.

Click here to see Google Images of Cylamen Mite damage on African violets

Mealybugs

If you’ve noticed white, cottony insects on your African violet, you have Mealybugs!  They have soft bodies and are covered with a white waxy material that makes them look cottony. They feed by sucking plant sap, and are found on leaves, stems, and leaf crotches. Their feeding causes stunted and distorted leaves, and heavy infestations can cause leaf and plant death. As they feed, they excrete honeydew (a sugary material) that can coat the leaves, making them sticky.

Prevention & Control:

Avoid bringing these pests into the house by inspecting a new plant carefully, including the bottom of the pot, for mealybug eggs.

Light infestations of mealybugs can be controlled by removing them with a cotton swab dipped in rubbing (isopropyl) alcohol. Repeat as needed.

Neem oil is a natural pesticide that's been used for hundreds of years on crops and houseplants alike. Repeat application in 7 days intervals until the mealybug is no longer present

Heavy infestations are more difficult to control with neem oil, as the waxy material that covers mealybugs protects the adults from insecticides. The immature nymphs are susceptible, however.

Pyrethins are a common ingredient in many houseplant and garden insecticides, and are effective against mealybugs. They are a natural product derived from flowers of a certain (pyrethrum) daisy. Pyrethrins are fast acting, have a very short persistence (a few hours), and low toxicity. Take the plant outside during mild temperatures to spray. Two or three sprays at three-day intervals may be required.

With any pest, it’s important to know when to call it quits. The risk Mealybugs pose to all your leafy companions makes trashing your African violet a pretty good idea if you have a severe infestation.

Click here to see Google Images of Mealybugs on African violets

Root and Crown Rot

Root and Crown Rot is one of the most serious fungal problems of African violets and is usually first noticed when the crown and roots of the plant turn soft and mushy. The older leaves droop, and the younger leaves in the centre of the plant appear stunted, turn black and die.

The fungi Pythium species and Phytophthora species can cause this, especially when plants are watered excessively, have poor drainage, or are planted too deeply. Any of these conditions can contribute to rotting of the crown and roots.

Prevention & Treatment:

Prevent diseases by always using sterilized potting soil mixes and pots when planting. Do not plant African violets too deep. Discard severely affected plants, and the pots they were growing in should be scrubbed clean and then soaked for 30 minutes in a solution of 1 part household bleach to 9 parts water before being reused.

Click here to see Google Images of Root and Crown Rot on African violets

Botrytis Blight

Botrytis Blight is caused by the fungus Botrytis cinerea and often first appears as small water-soaked lesions on the underside of the leaves. The leaves, stems, and even the flowers appear blighted, turning dark brown to grey, often with a fuzzy coating on the surface.

Prevention & Treatment:

Collect and discard all dead and dying plant material. Provide better air circulation, reduce humidity and avoid getting the flowers and foliage wet. Botrytis often follows mite injury, so controlling this pest aids in controlling this disease.

Click here to see Google Images of Botrytis Blight on African violets