Although silicon, a predominant element in mineral soil, isn't considered an essential nutrient for most plants, there has been limited evidence it might affect the aesthetic qualities of ornamental flowers.

Oklahoma State University researchers Sophia Kamenidou and Todd Cavins examined the effects of silicon supplements on sunflowers grown in greenhouse environments.

Cavins said the goal of the study was to determine the effects of silicon supplementation on the greenhouse-produced ornamental sunflower called "Ring of Fire" (Helianthus annuus L.).

The researchers found, depending on the source and concentration of silicon used, several horticultural traits improved as a result of silicon supplementation.

Kamenidou and Cavins said they observed thick, straight stems, increased flower and stem diameters and increased height in some of the treatments. "However, growth abnormalities were observed when concentrations of silicon at 100 mg and 200 mg per liter were supplied as potassium silicate substrate drenches," said Cavins.

The research appeared in the February issue of the journal HortScience and is available at http://hortsci.ashspublications.org/cgi/content/abstract/43/1/236.