For African violets, 'hands off' means healthier

November 3, 2009
For African violets, 'hands off' means healthier
People like to feel the soft, often hairy leaves of African violets, but touching the leaves can cause damage to the plants. Credit: Photo by Donna Dollins

African violets have a mixed reputation. Their delicate, colorful flowers and furry, soft leaves make them a favorite among home gardeners and growers. But the striking plants are often regarded as temperamental: a precise recipe of light, moisture, warm temperatures, high humidity, and fertilizer is required to encourage african violets to grow and flower.

A recently published study by scientists Julia C. Brotton and Janet C. Cole from the Department of Horticulture and Landscape Architecture at Oklahoma State University (in a recent issue of HortTechnology) could provide african violet enthusiasts with important care information about the finicky flower.

Because of their brightly colored flowers and hairy leaves, people are attracted to african violets and often want to touch the leaves and flowers. But how does all this attention affect the plants? The research team set out to determine the effect of "brushing" african violet leaves on plant growth and quality. Cole explained, "Because (african violet) growers work in conditions that can contribute to the development of dry, irritated skin, many growers use body lotions to help soothe and moisturize their dry skin. Many consumers also use these products. Our study researched whether touching or "brushing" african violet leaves causes damage, particularly when body lotion or other skin care products have been applied to hands before touching the plants."

Although previous studies have investigated the effect of various methods of mechanical conditioning, including brushing, on the growth and quality of vegetable and bedding plants, this was the first reported study of the results of plant response to tactile mechanical stress, or "thigmomorphogenesis" on african violets.

Plants of two cultivars of african violet (Saintpaulia ionantha), 'Michigan' and 'Gisela', received five brushing treatments during the study: no brushing, brushed for 30 seconds with a latex-gloved hand, brushed for 90 seconds with a latex-gloved hand, brushed for 30 seconds after applying lotion to a nongloved hand, and brushed for 90 seconds with lotion on the nongloved hand.

After five weeks the plants were harvested. At harvest, plants were rated on a scale of 1 to 5 (no damage - dead/near dead). Plants that were brushed by a gloved hand had lower damage ratings, greater leaf areas, and greater leaf numbers than plants that were brushed with a nongloved hand to which lotion had been applied. The cultivars varied in their response, with 'Michigan' exhibiting more damage from brushing than 'Gisela'

Summarizing the results, Cole remarked that "the study suggests that repeated brushing reduces plant size and quality of african violets, particularly when done with a bare hand to which lotion has been applied. Brushing leaves of african violets is not recommended because repeated brushing can decrease plant quality and size."

The next time you are tempted to touch that pretty african violet in your kitchen window, remember— for a healthier plant, keep your hands off!

Source: American Society for Horticultural Science

Explore further: Molecule tells flower to flower

Related Stories

Super plants may fight African hunger

May 24, 2006

Ohio scientists say they've produced genetically modified cassava plants with roots more than two-and-a-half times the size of normal cassava roots.

Buyer beware: Stressed plants won't survive shipping

December 3, 2007

It's a common springtime disappointment: you buy beautiful, flourishing potted plants from your local retailer, only to watch the once-healthy flowers wither and die shortly after you place them on your patio or porch. How ...

How size matters: The beauty of nature explained

December 12, 2007

The beauty of nature is partly due to the uniformity of leaf and flower size in individual plants, and scientists have discovered how plants arrive at these aesthetic proportions.

Recommended for you

Secrets of a heat-loving microbe unlocked

September 4, 2015

Scientists studying how a heat-loving microbe transfers its DNA from one generation to the next say it could further our understanding of an extraordinary superbug.

Plants also suffer from stress

September 4, 2015

High salt in soil dramatically stresses plant biology and reduces the growth and yield of crops. Now researchers have found specific proteins that allow plants to grow better under salt stress, and may help breed future generations ...

Ancient walnut forests linked to languages, trade routes

September 4, 2015

If Persian walnut trees could talk, they might tell of the numerous traders who moved along the Silk Roads' thousands of miles over thousands of years, carrying among their valuable merchandise the seeds that would turn into ...

Huddling rats behave as a 'super-organism'

September 3, 2015

Rodents huddle together when it is cold, they separate when it is warm, and at moderate temperatures they cycle between the warm center and the cold edges of the group. In a new study published in PLOS Computational Biology, ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.