Jeff McDanel never gets dirt under his fingernails. There isn't any to sully his hands in the greenhouse he maintains just south of Aiken.

The tomatoes he grows are strictly hydroponic, meaning they're grown without soil and get nutrients only as he waters.

It's such an effective system that his vines measure 45 feet long at the end of the growing system, with tomatoes as large as softballs, he said.

He planted his first hydroponic tomatoes 12 years ago in a backyard plot measuring 12 by 24 feet.

A few years later, he upgraded to a larger, computerized greenhouse that churns out up to 1,100 pounds of tomatoes some weeks.

Growing hydroponically is only a hobby for Mr. McDanel, an engineer, but he does sell some of his crop to Aiken restaurants.

Some restaurants in turn give him used vegetable oil, which Mr. McDanel burns to regulate the greenhouse's temperature.

The result is a 36-week growing season that produces large, flavorful tomatoes using fewer resources than traditional growing methods, Mr. McDanel said.

"(With traditional methods) you're more subject to the outside climate. There are so many more setbacks," he said. Hydroponics, though, is more of "an exact science."

In Mr. McDanel's greenhouse, tomatoes grow out of bins of perlite, a form of volcanic glass that substitutes for soil. Nutrient-rich water pumps into the bins, feeding vines tied to wires that stretch from one end of the greenhouse to the other.

A beehive sits in the middle of it all, naturally pollinating the 800 vines Mr. McDanel planted in November.

"It would take an acre of dirt to plant all this," he said. "Hydroponic is definitely the way to go."

Reach Kelly Jasper at (706) 823-3552 or kelly.jasper@augustachronicle.com.