Idaho-grown table grapes are small. The Treasure Valley industry that grows them in a stretch of farmland between Nampa and New Plymouth is small, too, with half a dozen commercial growers. But it’s expanding with the help of John Davis, owner and operator of two companies, Treasure Valley Grape Growers and The Dirt Doctor Inc.

Davis is a one-man-band for Idaho’s table-grape industry. Because of the small number of growers and their limited resources, Treasure Valley Grape Growers consults with growers to help them produce their crops on their 10-to 15-acre plots. It pools farmers’ resources to buy irrigation, packaging and other equipment.

“We work together with growers so we can afford supplies in a large enough quantity that we can get an economical purchase price,” Davis says.

As The Dirt Doctor, Davis sprays crops to ward off insects and pathogens. Last year, three of the vineyards Davis works with lost their crops to powdery mildew. “This year, they got involved in our spraying program, and they didn’t lose any,” he says.

All of this is virgin territory for the 3-year-old industry.

“It’s a new thing here, and we’ve had an awful lot to learn about weather conditions and cultural practices,” Davis says.

Southwestern Idaho has cool nights, long autumns and volcanic soil, which are prime conditions for the tiny, sweet grapes that grow here. Typical table grapes are between 17 to 19 Brix, a measurement of sugar in a solution. Idaho’s table grapes are between 22 and 24 Brix.

Mid-September through October is cultivation season, and this year, the six growers Davis works with have brought to market about 70,000 pounds of grapes, more than twice last year’s crop. The grapes sell at retail for between 88 cents and $1.48 per pound.

Harrison Berry: berryht@gmail.com