Lexington, Kentucky
June 24, 2009

Many gardeners plant zinnias because of their vibrant colors and ability to attract butterflies. In a recent study, researchers with the University of Kentucky College of Agriculture found butterflies are attracted to one zinnia cultivar over others.

UK Entomology Professor Ken Yeargan and Graduate Research Assistant Sarah Colvin found that Lilliput zinnias attracted more than twice the number of butterflies than State Fair, Pinwheel and Oklahoma cultivars during a seven-week period.

“Many people wish to include zinnias in their butterfly gardens so this study was intended to help them determine which cultivar to use to attract the most butterflies,” Yeargan said.

Adult butterflies are attracted to zinnias because they feed on their nectar.

Yeargan developed the idea for the study when he noticed the butterflies in his own garden seemed to be more attracted to the Lilliput cultivar.

“I’m not surprised Lilliput attracted more butterflies, but I am surprised at how much they were preferred over the other varieties,” he said.

Their study showed the most common species of butterflies prefer Lilliput over the others, and in most cases, do not favor any of the other three cultivars over one another. The only exception was Variegated Fritillary butterflies, which preferred Oklahoma zinnias over State Fair ones.

“I grew zinnias before, but never paid attention to which varieties were attracting the most butterflies. But when we were collecting data, we could pick out the plots that were Lilliput because of the number of butterflies attracted to them,” Colvin said.

The four cultivars used in the study were among the most commonly available in mixed colors. The researchers collected data from each of their 16 plots once a week in the morning and afternoon during the study.

Kentucky is home to at least 151 butterfly species. During the study, Yeargan and Colvin found 30 species and 2,355 total butterflies.

They are not sure why the Lilliput variety attracts more butterflies, but Yeargan speculates it could have something to do with the amount or quality of Lilliput’s nectar.

While Lilliput zinnias were found to attract more butterflies, Yeargan said butterflies must be in the vicinity of the plants in order to be attracted. Zinnias are not able to attract them from long distances.

Seeds of the cultivars used in the study are available at most garden centers or from sources on the Internet.

UK College of Agriculture, through its land-grant mission, reaches across the commonwealth with teaching, research and extension to enhance the lives of Kentuckians.

Website: http://www.uky.edu

Published: June 24, 2009