Christine's African Violet Page
Christine's African Violet Page
The African Violet (Saintpaulia) is the worlds
most popular house plant. Saintpaulia's history goes back as far as 1892, however it took years of development to get the charteristics that it is known for today. Research started in the late 1920's or early 1930's to develop the African Violet in to the the modern day version that is so popular today. This research and development has yeild plants with a variety of colored cultivars from blue violet, to fuchia, pink and white with more colors sure to come. These plants if cared for properly will bloom almost nonstop.
Lighting
Good lighting but not direct sunlight is needed for these plants to thrive. The African Violet does not necessarily need sunlight either, where there is not enough sunlight artificial light can be used and the plant can grow and bloom under those conditions. For optimum growth African Violets should receive 1000 foot-candles of light for eight to twelve hours each day. (A foot-candle is the amount of light given by one standard candle and intercepted on one square foot of surface.) Too much light can be harmful to African Violets however, it can cause slowed growth the plants leaves will turn to a pale green due to chlorophyll destruction and the flowering will decrease. Too little light can be harmful to these plants also the leaves will be a darker green and be noticeably thinner, they will also quit flowering or not flower very well.
Temperature
African Violets like a warm semi-humid climate. The temperature for African Violets should be around 60-70 degrees F at night. Cooler temperatures can cause plants to be stunted. The plants can grow well in in temperatures up to 80- 85 degrees F but if the plants are exposed to high temperatuers for long periods their flowering and growth are slightly stunted. In temperatures above 85 degrees African Violets have a high likelyhood of developing root rot. African Violets have been known to live in dry air climate but they grow and flower best in a slightly humid environment.
Soil
The African Violet needs soil that will drain well. A good mixture can be purchaced in some nurserys. However one should take care to notice that the soil is sterile. A good mix that can be made up is composed of two parts fertile loam, one part sand or perlite, and one part peat. A good growing mixture should contain 50 percent matter, 25 percent air and 25 percent water. A mix for African Violets should be porous and slightly acid with a Ph of around 6.0.
Watering
The soil for African Violets should be kept moist. When watering an African Violet one can water from either the top of the bottom but use water that is room temperature. When watering from the top be careful not to get the leaves wet, getting the leaves wet can cause spots or rings to appear on the plant's leaves. Also when watering from the top take care not to over water, get the soil saturated and dump out the excess water that drains through the pot. When bottom watering just put the potted plant into a container and adding about one inch of water, when the soil is saturated remove the plant from the container. Another way of watering is to just put a little water into the bottom saucer under the plant adding just a little every few days.
Propagating
The way to propagate an African Violet is to do leaf cuttings. It is recomeded to do this in the spring. Cut a mature leaf off the plant and for best results dip the end into rooting hormone, place the stem into vermiculite or other soil medium with the leaves slightly exposed, then water the soil well. Keep the cuttings moist and covered with plastic glass or muslin to keep moisture in. In 2-6 months young plants will have formed a few small leaves and are ready to be repotted. In 6-9 months the plants if cared for properly will begin to flower. To repot an African Violet gently remove the plant from the pot, trim off the lower row of leaves and scrape away the brown from the neck until just green is showing, have a clean sanitized pot that is about 1/3 the diameter of the plant ready and place the plant into it place soil around the African Violet, make sure to water well.
Pests and Diseases
There
are a number of pests that can harm an African Violet. One of them is root-knot
nematodes which cause stunting of growth and blisterlike galls on the roots
and leaves. Plants infested with root-knot nematodes should be destroyed.
Another pest that can 
harm
a Violet is the Cycamen mite which eat the plant crown and can cause the
new leaves to be brittle, lacking color, stunted and twisted. To destroy
these mites treat the plant weekly with dienochlor or with dicofol. Mealybugs
can cause injury to African Violets by stunting and distorting the leaves
because they suck all the juice out of the leaves and leave a sticky substance
behind called honeydew which can cause mold growth or ant infestation. To
get rid of Mealybugs simply spray the plants with warm water or remove them
by an alcohol dipped cotton swab. Aphids also leave honeydew behind which
can cause the plants to become stunted with curled leaves. To eliminate
aphids wash the plant with warm water or treat with an incecticide.
Some other problems that can occur with African Violets include Botrytis cenerea and powdery mildew. The fungus Botrytis cenerea can be found in African Violets grown in green houses or in a room with high humidity and little air circulation. The fungus causes the leaves to turn dark brown. To control this use a fungicide for plants. Powdery mildew shortens the flowering of the African Violet and is characterized by a grey powdery substance on the plant. This is caused by cool damp air and can be stopped by karathane or can be prevented by a small fan to circulate air.
Diseases
such as chlorosis or ring spot, petiole rot and root and crown rot can be
easily avoided by taking precautionary measures.
Ring
spot is characterized by white or yellow rings and lines on the leaves is
caused by sun shining on wet leaves or by cool water touching the leaves.
To prevent this water the plants by the bottom method or be sure to use
water slightly warmer than the air and not drip on the leaves. Petiole rot
is a rusty colored lesion where the petiole touches the soil or the rim
of a pot that has accumulated fertilizer. To prevent this a ring of aluminum
foil can be placed on the pot and by occasionaly watering the African Violet
heavly to wash out the excess fertalizer. Root and crown rot is caused by
Pythium ultimum a fungus which comes from overwatering plants the
crown and roots turn dark and the leaves wilt. If this is not avoided all
infected plants must be destroyed.
"Space Violets"
Optimara a leading company in African violet research and development launched its "Space Violet" program in 1984 when Holtkamp Greenhouses (developer of Optimara violets) sent 25,000 seeds into space. These seeds orbited earth for six years finally being retrieved in 1990. Not long after mutations became visible, some which are still in development. One such mutation is multifloresence.
References
