African Violets or Saintpaulia come from eastern Africa specifically Tanzania and Kenya. There are many cultivars to choose from. There are so many different flower shapes, colors of flowers, multicolored varieties, trailing cultivars and even miniatures that it could keep the collector happily busy for a long time. After discovery by the western world in the late 19th century African Violets quickly became a popular houseplant because of their potential to flower for most of the year. Due to their small size and relatively easy care, with a little attention anyone can grow an African violet successfully.
Light and temperature (and humidity)
The intensity of the light is much more important to African Violets than the duration. It is important to provide a location that has bright indirect light, never direct sun, with temperatures that will not get too warm. To accomplish this put your plant a few feet to the side of a south or west facing window. If you have to put it directly in the window keep a sheer curtain drawn at all times and watch that temperature. A good location would be about a foot from an east window where it will receive enough light without the dreaded heat. Find the brightest light, without direct sun, and temperatures below 85°.
During the winter you may need to add a light source to keep them thriving and flowering through the winter. You will need 600 foot candles for 12-15 hours a day from artificial source if measuring this way. Two, 40 watt florescent bulbs placed about 1′ above provides this.
Temperature should be kept between 62°-72°F (16-22°C). At higher temperatures African Violets dry out quickly but colder temperatures are the real danger. Evaporation of water from the soil is critical to avoiding rot in your African violet and as temperature drops so does the evaporation rate. As the temperature of the air drops so does the temperature of the soil and the roots have more difficulty absorbing the nutrients they need. Do not let this plant become chilled. You may have to move it away from the window at night. Cold drafts can cause curling leaves and other problems. Dry warm drafts from forced air furnaces can cause buds to drop or flowers to fade quickly.
The humidity level that African Violets get in their natural habitat is quite a bit higher than in the average home. There are a few things you can do to raise the humidity around your plants. Grouping plants together helps to raise humidity as does using a pebble tray. The average American home can have a humidity level as low as 15% and your African violet will thrive with 40%-60% so do all you can for the best results.
African violets are sensitive to getting water on their leaves so watering should be done from the bottom if possible. Water on the leaves invites fungal growth. Place the pot in a tray of water and allow the water to absorb into the pot through the drain holes. Remove any water remaining in the tray after about 30 minutes. You do not want the pot to sit in standing water too long. If you are using a pebble tray you can run a wick through the drainage holes and down into the water in the pebble tray. Just be sure that the pot is above the water level. Use room temperature water. Put water into your watering can the night before you intend to water. It will be the right temperature and the undesirable chlorine you may have in your tap water will evaporate. Chloramine can be neutralized with chemicals from your local aquarium supplier. Water on the leaves just invites fungus growth.The soil should dry about 1″ down between waterings and never allow to become soggy. When watering from the top, get under the leaves with the spout of your watering can, and water when dry about 1” down.
When creating a soil mix for African violets you will need to provide a mixture that is similar to the very porous mix in their natural habitat. Few African violet growers use a soil based medium. I can recommend a soilless mix of 1 part sphagnum peat or coir, 1 part vermiculite and 1 part perlite. Do not tamp down too firmly or you may damage the fine fibrous roots. You may add 1 T dolomite limestone per gallon to buffer the acidity and neutralize the fluoride present in the perlite. Moisten the mixture before you put it in the pot so the roots aren’t stressed. Making the effort here will help you on your way to happy, healthy violets.
African Violets need a nutrient rich medium so fertilizing regularly is important. For a typical cultivar use a diluted, half strength, balanced liquid fertilizer 15/15/15 or one high in phosphorus,15/30/15. Be sure to flush the soil of any mineral deposits left by the previous feeding about a week before you fertilize again. You can get into a nice routine and water with clear water once, then water with a ½ dilution of fertilizer the next, then back to clear water. Too much fertilizing is a danger to this plant. Feeding can be done at every watering, especially for someone who can’t remember when they may have fed their plant last, using a ¼ solution.
A location with bright light that is not too warm, soil that is not permitted to dry out – especially when buds are forming, and extra added humidity are the basic requirements for producing flowers. Constant growth indoors requires constant nutrients. *Keep your violet fed and flowers should bloom for you.
The use of florescent lighting can be an enormous help if you do not have enough natural light. It should be placed about 10-12” (25-30 cm) above the plant and left on 10-12 hours a day. Water your plant when dry to the touch. A violet that is blooming like crazy will require more water than one that is not. There can be a fine line so just keep an eye out. The wicking method can be beneficial for you if you’re not sure when to water. A pebble tray is an easy way to raise the humidity around your plant.
When you bring your violet home, give it a few weeks to acclimate, and then think about re-potting it. A grower may use a potting mix that is cost effective for mass production and is heavy enough to help prevent a plant from spilling over in shipment. Your plant may do better with a lighter mix. If the medium looks like peat only you can add vermiculite, perlite or pumice to make it more porous. African Violets are not fussy about when you re-pot but re-potting during active growth is best. You can usually tell when they are actively growing and producing new leaves.
Re-potting your violet as often as every 6 months can be beneficial. You should re-pot when the base of the plant is over an inch above the soil (this is natural) or the leaf spread is more than 2/3’s beyond the pot. You may find that it has developed additional crowns, these should be divided or removed.
A proper violet pot is more wide than deep and with a deep saucer of stones to sit on you can provide both humidity and a way to water from the bottom so you will not get water on the leaves. The pot diameter should be 1/3 the size of the plant.
On a day when your plant is a little bit dry, take your plant out of its pot. Remove the soil while being careful of the delicate root system. Remove any aging, spotted or wilting leaves. Using the medium ingredients above, fill the bottom 3rd of the pot. Place your plant at the height you want it, center the crown, and gently fill around the roots tamping very lightly as you go. Give your plant a nice drink and empty the runoff water.
If you are re-potting because the lower leaves have been removed and the resulting neck is long you will want to scrape the calluses off the neck and get to expose soft tissue. This will allow roots to form more easily. It also may be a good idea to trim the fibrous roots and taproot a bit so you can get the plant back into the proper size pot. Toss the rest. Perhaps 1 ½” (4 cm) will remain – you need to put the entire neck under the soil.
Once your plant is in its new soil, place a cover over it to increase the humidity and raise the temperature for a week or two and up to a month, especially if you have removed a lot of its roots. You will only need to add water if you do not see condensation.
If you are re-potting because of an ailing plant but it still has flowers, it is best to remove them, re-pot, and let the roots have all the growth focus.
Propagation is done mainly by leaf cuttings so when you re-pot you should also trim off some of the outer leaves, make your cut so you have about an inch of petiole (leaf stalk) to bury in the medium. For the best results leaf cuttings should be rooted in 100% vermiculite or sand or even a 50-50 mix of each. You may get several little new plants from one leaf. It may be desirable to choose only one and discard the others if you want one plant in the center of the new pot. Use about a 2″ pot for the new plant.
Dividing a plant that has multiple crowns can be a tricky affair. You must, very carefully separate them, with a very sharp knife, while ensuring you get root with each cut. These are each placed in its own pot and covered to create a very humid atmosphere until they each root. Give them some fresh air each day so they do not mildew.
Problems and pests
The most common problem people run into is rot caused by over watering. Be sure the soil is dry and always water from the bottom to avoid getting water on the leaves. Other moisture related problems are also common like powdery mildew and Botrytis blight (a fungus). Poor air circulation, both above ground and above, is usually the cause of these infections.
The leaves are quite thick and fleshy. If you find your leaves are thinning or the petioles are longer than you think they should be your plant is probably not getting enough light.
If you have faded leaves, a lighter green than normal, it may be due to lack of nitrogen available to the roots due to temperatures too cool or there is just not enough nitrogen in the soil due to the feeding schedule. Be very careful not to over fertilize. You may get an abundance of flowers but your plant will pay in the long run with leaf damage.
Tight distorted centers may be a sign of fertilizer build up.
Spider mites, Cyclamen mites, thrips, and mealybugs can also cause problems for African Violets. These pests can be so tiny you may not see them but you may see evidence of them. Flowers that fade prematurely may be thrips, small flowers or stunted center foliage may be mites. These can be hard to deal with as you don’t want to get water on the leaves. The best way to get rid of these pests is with a cotton swab and tepid water or rubbing alcohol.
You may see a flour like substance on the leaves. This is powdery mildew. The nice humid atmosphere you provide is also attractive to mildew. Keeping the air moving and at as constant a temperature as possible will.help discourage this problem.
Some African violet hobbyists find benefits in adding horticultural charcoal to the medium to increase porosity or layer it on the bottom of the pot.
Re-potting a plant when a bit dry will help prevent the leaves from braking off even while you’re handling it gently. The leaves are less brittle at this time.
Remove old, soft leaves from the plant to help discourage root rot.
Miniature varieties should never be in a pot larger than 2-3” in order to keep the plant small.
*There are, of course, times when you are doing everything right and your violet still will not bloom nicely for you. This is probably genetic. Time to replace your plant and talk to a grower to get a variety and a plant that will make you happy.