Quiet grape harvest due to last year's wicked winter

Posted at 8:47 AM, Oct 24, 2017
and last updated 2017-10-24 10:47:56-04

Fall harvest season is typically a busy, bustling time of year at Williamson Vineyards in rural Canyon County. But this year, it’s all too quiet among the vines.

That's because, according to Vineyard Manager and 4th-generation grape-grower Patrick Williamson, the plants are still reeling from the rough winter they endured earlier this year. “Here at this location, I got down to minus 17 degrees [in January 2017]," Williamson recalls.

Temperatures that frigid can -- and did -- have a destructive impact on the grapevines. Williamson explains it this way: "Think of it like a pipe. It freezes, the water in the cells bursts, causes the cells to die once they thaw out."

That, in turn, leads to vines that have to work much harder than usual to grow once it gets warmer. "So we have in some instances a 20 year old root system, so it'll grow back and come back, but the canopy...still needs to get established," says Williamson.

It also means the plants don't produce much fruit the following fall. So one bad winter actually has a 2-year impact on the vineyard's harvest. In fact, says Williamson, “There really is no crop to give this year…So not in '18 but in '19 we'll be back to full production."

Another unexpected and unwelcome consequence of the record-setting winter - a disease called 'crown gall' that can develop in plants that have gone through a severe freezing event. "It's like a cancer that is going to eventually kill the vine."

The bacteria that causes the disease is ever-present in the soil, but severe winters cause damage to the vines that allows the bacteria to get in. Williamson says he can save the plants from the disease, as long as it's caught in time. “...You can cut up above, or cut the crown gall out, and the new growth above that is gonna be free of that infection."

As far as snow goes, Williamson says the snow that blanketed the ground for weeks out in the Sunnyslope area actually helped save the vines from further damage. The packed powder acted as an insulator to protect the root systems from the frigid conditions. Without it, the impact of the severe winter conditions could have been much worse.

Now, as winter approaches once again, the Williamsons can't do much but wait and see what Mother Nature doles out this time around. Patrick, though, seems optimistic about their chances."As long as those roots are protected we should be okay. That's the nice thing about grapes,” he jokes, “they're a weed that you can make money off of.”


For more information on the Williamson vineyard, visit their website, and to learn about Idaho’s booming wine industry, check out the Idaho Wine Commission.