African Violets and Gesneriads: I'd like to talk about light and African violets :)), 1 by Allison_FL

Allison_FL wrote:
**** Did you know Light is one of the most important recipes in the growth of your African Violets? ******

Did you know Light is one of the most important recipes in the growth of your African Violets?

Light is the only form of energy, so far as we know that will initiate the process of Photosynthesis.

You ask what is Photosynthesis?
Photosynthesis means manufacture by light. This process takes place only in the green parts of plants. A plant leaf is a factory that captures the energy of light, enabling the plant to absorb carbon dioxide from the air and combine it with water to absorbed by the plant's roots to make carbohydrates. These are chemical substances from which all other foods and all parts of living cells are made.

With out the correct amount of light you can feed your plants all you want the food won't work ...African Violets need plenty of light ~ What is Chlorophyll you ask?
It is the green stuff in all vegetative matter that captures and uses the energy of light to convert air and water by photosynthesis into sugars and starches.

Do all plants need the same amount of light?
No. Various plants require different amounts of light, for different periods of time. Geraniums need more than gesneriads, for example and among other gesneriads, African violets need less than gloxinias but more than episcias.

What kind plant is the African Violet, in regard to its light requirements?
It is an indeterminate or daylight, neutral plant, that is, it does not require a specific number of hours of darkness or light to flower and set seed, but will do so under a wide range of day lengths.

Which is best for violets, natural daylight or fluorescent light?
Either light will grow fine violets if culture is good. With natural light in east window is preferred. Plants can be grown properly in south and west exposures only if the light is filtered on bright sunny days.

My plants are in both natural and grow lights as their stands are blessed to be in a room full of windows should my plants ever have direct sunlight?
Yes During the dark days of midwinter, mild sunshine (but not glare from Snow) is beneficial and encourages growth and bloom. During other seasons, African violets must be protected from lengthy exposure to direct sunshine.

Will screen left up during the window, reduce the amount of light?
Yes. During the dark days of winter, screen will reduce window light by 25 to 30 percent... dirty windows and dirty leaves will also reduce light.

When my plants are most in flower, my foliage looks the worst. Why is this?
No doubt your plants at this pint are enjoying an abundance of strong light and sun. This is marvelous for flowering plants, however, violet foliage is very tender and the sun bleaches out much of the chlorophyll in the foliage, leaving it pale and limp. You should find a way of adjusting light without cutting it.


African violets are grown all over the World with Artificial light alone. It is almost ideal way to grow fine, heavy-blooming plants year round!

Do plants under fluorescent light require more fertilizer than plants in a window?
Yes they do, because they are constantly growing. In daylight a plant is governed by the season; but under fluorescent lights you are creating and ideal growing season, so you must give the plant conditions accordingly. A healthy, blooming plant shows perfect balance of light, food, humidity, temperature, and water.
Twelve hours a day or more of Fluorescent lighting is great for African Violets.

Does a fluorescent tube emit the same amount of light along it's full length?
No... Light output falls off at both ends of any fluorescent tube, due to its internal construction and the blackening due to use. It is best, therefore, to use the longest fixture and lamps possible. If you have 100 inches in length to illuminate, use one fixture with 96 inches tubes rather than two fixtures of 48 inches end to end.

How often should fluorescent lamps be replaced?
Bulbs should be changed about every 15 to 18 months, or when dark rings appear at the ends of the tubes, whichever comes first. I belong to a local group and everyone show plants so they replace their light tubes once a year. Also when replacing them do one per fixture at a time next week do the other so your plants don't go into light shark.

Are Gro-Lux lamps expensive?
They cost twice as much as standard white fluorescent lamps, however with Gro-Lux lamps you get back in radiant energy usable by African Violets nearly 100 per cent of the electrical power you put into the lamp. From conventional white fluorescent lamps you get in usable radiation about 50 per cent of the power you pay for - the rest goes into radiation that plants do not need or use.

What can I expect if I switch to Gro-Lux lamps?
The first thing you will notice is the dramatic change in the appearance of your African violets! Every bit of flower color enhanced and foliage looks lush and vibrant and exceedingly healthy. Within a week you will see that they actually are growing better.

How many hours of light?
How many hours of fluorescent lights are needed by African violets each day? Generally 12 to 14 hours a day, and additional hours up to 16 hours do not seem to harm them and is good getting ready for show.

Should I burn my fluorescent lights over my violets the same number of hours everyday of the year?
Reduce to 10 to 12 hours during periods of extreme heat. Here in Florida I turn mine off by noon and run them at night when it's so hot out So many of my girl -type plants tend to knot up in the center when grown under lights.

Does everyone have this problem or am I doing something wrong?
I can't say if everyone has the difficulty but I know I do. I have tried giving them less light, shorter hours, covering the crown, and still have not been able to get over the difficulty. I found the solution seems to be place the girl leaf plants near the end of the fluorescent tubes where the light is not as strong, or group them together and give them shorter hours of light.

What are the symptoms of insufficient fluorescent light?
The leaves will grow upward.

What are the symptoms of too much fluorescent light?
The plant will bunch and tighten in the center and turn gray-the symptom is much like that of an infestation of cyclamen mite. Too much light can also cause variegated African violets foliage to revert to solid green; technically this amount to making a sick plant well again because the variegation in a plant foliage is actually an abnormal distribution or absence of chlorophyll.