Idaho potato growers concerned about crop heat stress

Extreme heat throughout Idaho to start July has raised concerns from some potato and onion growers.

Idaho farmers are worried prolonged above-normal temperatures may have stressed or damaged certain crops, especially onion fields already weakened by iris yellow spot virus and Russet Burbank potatoes.

According to the National Weather Service, temperatures for the first 14 days of July averaged 8.6 degrees above normal in Boise, where daily highs exceeded 100 degrees from July 11-14. Temperatures during the first two weeks of the month averaged 8.5 degrees above normal in Twin Falls, 6.2 degrees above normal in Burley, 5 degrees above normal in Pocatello and 4.7 degrees above normal in Idaho Falls.

Randy Hardy, a fresh Russet Burbank grower in Oakley, said temperatures on his farm reached 101 on the afternoon of July 14. He’s been equally concerned about early morning temperatures in the 70s.

“What makes Idaho potatoes as good as they are is we have heat, but we don’t have extreme heat, and it cools off at night,” Hardy said.

He believes high temperatures may have taken the “edge off” a crop that had been about 10 days ahead of schedule and set a large number of tubers.

“You may see some fields coming down earlier than normal,” Hardy said, adding heat could contribute to rough skin, odd shape or high sugar levels at the ends of Burbanks.