Published on 04/26/07

Years of research net list of Deep South conifers

By Brad Haire
University of Georgia

John Ruter's Northern colleagues told him the summers were too hot and winters too short for ornamental conifers to thrive way down South. He'd waste his time. But he's proven them wrong and is ready to offer some much-needed diversity to Southern landscapes.

Conifers are cone-bearing woody plants -- mostly trees, but there are a few shrubs. Cedars, spruces, pines, junipers, redwoods and firs are examples.

It's true, he said: Northern states' climates support more diverse conifer types than Southern states. Certain conifers just won't thrive in coastal plain regions like south Georgia.

The climate and soil are different even from those found as close as Athens, Ga., said Ruter, a research horticulturist with the University of Georgia College of Agricultural and Environmental Sciences.

When most Deep South gardeners think about conifers, they picture pollen-pumping pine trees dropping messy cones in their yards, he said, or disease-prone Leyland cypresses flopped on the ground from a gust of wind or heavy rain.

That's a shame.

Ruter began trials 10 years ago at Savannah and the CAES Tifton, Ga., campus that included 250 varieties and species. He did it, he says, to prove his doubtful counterparts wrong. He did it partly to prove "that you can grow conifers with yellow or blue foliage down here" and partly because Southern nurserymen were calling for the research.

He didn't plant conifers more commonly found in the northern United States. He knew they wouldn't work. So he planted ones native to subtropical climates in Southeast Asia and Mexico and a few from places like the Himalayas and Siberia, "which have done surprisingly well," he said.

After helping the plants get established with a little drip irrigation, "we basically just let them go to see which ones might work or might be adaptable to the Southeastern United States," he said.

He studied the plants for diseases, pests and mortality and took note of their growth habits, color and seasonal interest. He measured height, width and stem diameters.

Of the 250 original plants, 75 percent survived, he said. "But not all of them are commercially acceptable, for one reason or another."

He studied them for 10 years "because that's a good time period to evaluate a plant to see if its going to be suitable for a particular region," Ruter said.

Now, he has 10 "really neat" cultivars he says Southeastern nurseries should consider growing. They include some pines, cedars, cypresses, redwoods and a fir.

"The next step will be getting these plants into nurseries and out to the end consumers and seeing them in the landscape where the average homeowner will have some diversity," he said.

Ruter and a large Georgia nursery are working out a deal to do just that.

He plans to cross the conifers in his collection to create new kinds for future release. He's also collaborating with Tom Cox, president of the American Conifer Society, on a book about conifers for the Southeast.

Georgia's ornamental horticulture industry has a value of about $700 million annually.

Brad Haire is the former news editor with the University of Georgia College of Agricultural and Environmental Sciences.