The sweet potato that McRay Greene Jr. holds out is normal in all respects but one: The color of its skin is a deep purple. And when he cuts it open, the flesh is purple as well.

The Walnut Cove, N.C., farmer is part of a small group of farmers in the northwestern part of the state who are betting that a purple sweet potato will be a profitable alternative crop.

Greene needed an alternative. He had a long career as a flue-cured tobacco grower, but found it much less attractive after the quota buyout.

“Sweet potatoes grown for a gourmet market look better than tobacco right now,” he says. “If we can keep the diseases out, there's a whole lot less management involved than in tobacco. You don't have any of the intense tobacco practices like topping, priming and curing.

“I think I can make more per acre on sweet potatoes than on tobacco. If we can come up with an added value product, that will be even better.”

The impetus for the purple potato has come from Mike Sizemore of Walnut Cove. After retiring from state government a few years ago, Sizemore returned to Stokes County, where he owned some property.

“There were tobacco fields all around,” he says. “We didn't want them turning into pine thickets, so we needed a new crop. We looked at grapes initially, but startup seemed cost prohibitive. Also, grapes are very labor intensive, and then we would have to wait five years for a saleable crop.”

So he started looking for something else, and conventional orange sweet potatoes struck him as a good candidate. He grew a test crop in 2003 and was satisfied with the results, and he has grown several crops since. He later started growing a white variety of sweet potato.

Then, another possibility turned up unexpectedly. Sizemore was approached by a farmer from the north end of the county who had been producing sweet potatoes since the 1940s.

“Russell Slate of Lawsonville was looking for someone to grow potatoes for the clientele he had developed,” says Sizemore. “He said if we would agree to grow potatoes on his farm to continue the tradition and to take good care of customers he had developed, he would give us his business, including harvest bins and other equipment.”

There was an added bonus: Slate also gave Sizemore some slips of a purple sweet potato that Slate had come across by chance. Sizemore thought it was worth developing. He formed a company that he called Saura Pride to develop and sell the purple vegetable, along with orange and white sweet potatoes grown in the county as well.

“We contacted North Carolina State University and put the purple variety into the micropropagation program to clean it of any plant viruses,” he says. “We paid the fee for exclusivity, and that gave us the right to name it. The name we chose was Stokes Purple, which we have since patented. Now, we think we can develop it into an important cash crop for this county.”

Sizemore has contracted with three growers for 2007 and may contract with a fourth.

“We would like to grow 10 acres,” he says. “We are paying a good price, enough that we think they can clear more than they would on tobacco. We are looking for growers with red clay soils who are willing to follow good farming practices.”

To date, all the Saura Pride farmers have had prior experience growing sweet potatoes.

Wireworm control and nematode control are very important, both for yield and quality. The company helps by providing a rig to inject chloropicrin and bed up right behind it. The farmers pay for the chloropicrin used on their farm.

“We have learned what a difference fumigation makes,” says Sizemore. “Two years ago we planted a strip and didn't inject chloropicrin, and we got eight bins of potatoes. Last year, we grew potatoes on the same land and treated it the same way, except that we injected the chemical, and we got 12 bins.”

Another key practice is careful gathering. A farmer has to be willing to harvest with tender loving care. “You have to put them in the bin carefully,” he says. “This crop has to look good.”

A good labor supply is a must, he says. “I have to hire a small army to harvest.”

Once harvested and cured, the Saura Pride potatoes are hand washed and nipped off at the ends for a clean neat look.

At this point, Stokes Purple is relatively low yielding. A good crop might yield 15,000 pounds per acre, while 20,000 pounds and up is a realistic goal for orange sweet potatoes in the eastern part of North Carolina.

But Stokes Purple has some health benefits that may help it with informed consumers. “The Vitamin E content is 8.5 times that of an orange sweet potato, and it also has more Vitamin C,” says Sizemore. “But it does not have the Vitamin A beta carotene that makes an orange sweet potato orange.”

Still, says Sizemore, the color is going to be the primary selling point.

The variety has a bit different flavor from conventional sweet potatoes, but the difference is hard to describe. But Sizemore has noticed that when baked, Stokes Purple isn't as moist as the orange potatoes.

At the same time the company has been developing Stokes Purple, it has been growing marketable quantities of the Beauregard variety of orange sweet potatoes and the O'Henry variety of white sweet potatoes.

“We have some loyal customers already for our Beauregards and O'Henry's,” says Sizemore.

But 2007 is the first year of serious marketing of Stokes Purple. Local groceries, restaurants and food companies are among the markets that Sizemore is trying to cultivate.

The purple sweet potato will definitely be a niche market product rather than a commodity, says Nick Augostini, marketing specialist for the North Carolina Department of Agriculture.

“The upside of a niche market is you can demand a higher price for the product,” he says. “The downside is you have to work really hard to create your own market. You have to be able to take rejection well. For every 50 doors you knock on, you may get 49 no's.”

But one thing that may work in favor of Stokes Purple, says Augostini, is that buyers often look for different fruits and vegetables to “consolidate” a truck load. Since the Stokes farmers are growing orange and white sweet potatoes, buyers may appreciate having another product to load.