PLACEMENT OF PLANTS

By Nancy Robitaille

Space between plants is important for the healthy, good growth of African violets. Placement on light stands is another important factor to contemplate.

Two schools of thought prevail and these are directly opposed to each other. Therefore, it is wise to use your own experience to decide just where that particular plant should be based.

The older school of thought is that dark foliage plants and dark colored flowers on plants need more light; place them in the middle of the light stand. Light foliage and light colored flowers prefer less light; place them on the outer edges of the light fixtures.

If you have light stand(s) you must consider where each violet would best be placed for maximum growth as well as where it could best be displayed for your own enjoyment and that of visitors or family members.

As far as I know, there are no hard and fast rules as to where to place different varieties on light stands. It’s a matter of logical thinking about the attributes of the plants and their needs and where these can best be met.

If we make up a general chart about plant placement using the ideas from the old school, it might look something like this:

Dark foliage plants need more light (exception Optimara plants which seem to grow well no matter where they are placed—even in window light) Place these on centers of each shelf.

Dark colored flowers such as blue, purple and red seem to thrive with more light.

Light foliage such as Apple green foliage and girl foliage need less light. Place these at the ends of each shelf of light garden.

Light colored flowers, pink, white, yellow, green do well with less light.

To support this school of thought, Helen Van Pelt Wilson’s AFRICAN VIOLET BOOK, Hawthorn Books, Inc, publishers, 1970, page 70 says: “Fluorescent tubes do not emit the same amount of light throughout their length. Light comes strongest from the center, falling off at the ends. Because of this, you want to select as long a tube as possible, to have the advantage of a long bright center.

“ Light requirements vary with African-violet varieties. Some need more light than others. Experience is the best guide as to where to place your plants on your shelf or bench—in the center for maximum exposure, at the ends of the tubes for less. To give examples by varietal name is not feasible, but here is a rule of thumb: The darker the leaf the more light it will usually absorb, so place dark-leaved varieties under the center of the lights. Plants with pale leaves and white or light-colored flowers, also miniature plants, should generally go at the ends of the tubes on the outer edge of the bench or shelf. But this is not a hard-and-fast rule because some varieties will surely contradict it.”

Plants will tell you if they are receiving too much light. Leaves that are bleaching out or paler than normal indicate that the plants should be moved to a less intense position on the light stand. Often leaves that hug the pot or turn down are signaling their unhappiness in the present position. Some varieties will get tighter centers which look similar to cyclaman mite outbreak when they are only saying that the light is too intense. Some variegated plants may turn green when too much light is absorbed.

“The distance between plants and lights must also be taken into consideration. Measure from the top of the plant, not from the shelf or from the top of the pot. General experience indicates that a good distance for mature plants with dark foliage is 6-8 inches under white lamps, about 10 inches below the growth lamps, but distance is really dependant upon plant response. ...My own experience under growth lamps seems to be most favorable at 7 inches for standard plants, 5 inches for miniatures...”

“You might start with 10 hours of illumination and work up to the usually acceptable 12 to14, even to 16 hours. My plants, standards and mini’s, rarely get more than 14 hours.” 

(EDITOR: NOTE SPELLING OF MINI’S IS QUOTED AS PUBLISHED IN BOOK)

Wilson states that gesneriads such as episcias grown for flowers and not just foliage should be placed in the center of the shelf where they can receive light from all sides as well as from above. Gloxinias need more light than African violets.

NEW SCHOOL OF THOUGHT 

Now, the new school of thought about placement of African violets on floral carts is as follows:

“GROWING TO SHOW-- How to Grow Prize-winning African Violets” by Pauline Bartholomew, AV Enterprises Press, 1987, page 27. 

“Place light-colored foliage plants near the center of the tubes under the strongest light and dark colored foliage at the ends of the tubes where light intensity is weakest. Light-colored foliage plants placed at the ends of the shelves lean noticeably into the light within about 12 hours. Dark-colored foliage plants remain stable for many days at the ends of the shelves and require much less turning. A possible explanation for this phenomenon is that light colors reflect light and dark colors absorb light. Thus, perhaps the dark foliage is utilizing the maximum benefit of the light and light foliage is losing some of the ligh benefit through reflection.”

...”Leaf cuttings, plantlets and miniatures should be about 6” to 8” below the lights. Even at 10” to 12” below the lights, plantlets and miniatures have a good growth rate and will stay flat and nicely shaped, but they will have few blossoms. Mature plants should be placed about 8” to 10” below the lights.”

Since two such excellent growers and authors of African violet books are in opposing corners, it might be difficult to choose which should work best. Testing for placement is easy enough to do. Be your own judge after a few months of testing each theory.

Plants may be raised for greater access to light by placing them on containers, whether or not they are to be wicked.

Variegated plants need special attention. Whatever variegation is involved, Tommie Lou or Crown, they both need high intensive light, and this means they want center stage, lower shelf (for coolness). (Mosaic variegation seems to grow well with less light than other variegations.)

Plants with wavy foliage thrive in places of less intense light. Center of the tube seems to make these plants tighter which may or may not be desirable.

Minis and semi-minis need to be closer to lights to develop those perfect rosettes and intense variegation. They should be approximately 5-7 inches from the light tubes, either in center tubes or at second best very near center giving places of preference to variegated varieties.

The problem develops when a plant has dark foliage and a light colored flower. Where should these be placed? I would try these in a position just off center of the tube.
A plant with light green foliage and darker colored flowers do well at the ends of the tube.

Fantasies are another problem. Where should these be placed for maximum growth?. Intense light MAY make these colors more vivid. However, bi-colors such as pinwheel chimeras seem to do well on the ends of light gardens especially when foliage is light colored.

The usual light fixture set-up is one cool white/warm light on each shelf. If growing for show, fluorescent light bulbs should be changed each year perhaps 2 months before show. Since new bulbs make the light more intense, put the new bulb in in the evening and use if for an hour or so only for the first time. Be sure to mark the date on each bulb. Those growers who do not take plants to show can use the tubes until they turn dark at the end. 

What do other authors say about placements of plants in the light garden? “How to Grow African Violets” Sunset Book , Lane Publishing Co. Copywrite, 1977, page 27 says:

“Set mature plants of dark-leaved, dark-flowered, and double-flowered varieties 6-8 inches from special growth lamps. Arrange varieties that require less light—such as plants with variegated or girl-type foliage or white or pink flowers—around the edges of the lamps where the light is less intense. Place miniatures on inverted pots so they stand about 5 inches from the light source.”

CONCLUSION
Confused? Well, that just means you have your work set out for you. You make the decision as to whether you will use the old school of thought or the new. My own plants have done very well with the old school’s teachings; however, there is always room for improvement.