A tough harvest is translating into a challenging storage season for Manitoba potato growers.
It’s especially frustrating because growers were looking at a bumper crop, forecast to be the third-largest harvest on record. But they were denied that by rains that delayed harvest and hard frosts that hit in mid-October causing ground to freeze as deep as three inches and ultimately leaving more than 5,000 acres, causing Dan Sawatzky, Keystone Potato Producers Association manager, to describe the situation as “unprecedented” in the province’s 50-year history of growing potatoes.
Why it matters: Industry insiders say the toughest potato harvest in a generation set the stage for tight storage supplies and also created potential problems with storing this season’s crop. Now as winter wears on growers are seeing those issues arise.
“People were scrambling to dig that crop even in conditions that were maybe not the most ideal, so we are seeing additional storage losses that we may not have seen under better conditions,” Sawatzky said at the recent Manitoba Potato Production Days in Brandon.
Storage challenges are no surprise to those growers who took a chance on salvaging frost-damaged crop. Producers were piling late-dug potatoes lower than normal, Sawatzky noted, something that he now says is saving some of those smaller, low-piled sheds.
Those frost-damaged potatoes will generally break down in storage as the waterlogged tissue provides a host for rot, Leonard Rossnagel of the Manitoba Seed Growers Association said.
“One thing that producers have been doing is keeping temperatures lower in their storages and putting as much air through the pile as they can — the extra air through the pile to dry up these tubers and the lower temperatures to reduce the activity of the rot organisms,” Rossnagel said.
The challenges are not limited to frost-damaged tubers, however, and Sawatzky reports that some early-dug potatoes are also facing more spoilage due to wet harvest earlier in fall.
“We realized that we would have some issues,” Sawatzky said, later noting the number of producers working to circulate fresh air and heat-dry potatoes during November. “The processors have worked very hard to try and salvage and use what they can, so they’ve been working maybe a little closer (with farmers) because the need is there for them to use what they can.”
In November, Sawatzky told the Manitoba Co-operator that processors were working with producers on issues like fry colour, although he stresses that those processors must still meet their quality specifications.
Rossnagel says he has heard some producers complain of storage issues in sheds they initially expected to weather the winter.
Manitoba’s recent cold weather has only increased the spoilage risk. A polar vortex sent temperatures plummeting below -30 C throughout Manitoba in late January, with some overnight lows inching towards or beyond -40 C.
“The fans will run, pushing air through the pile, all the time,” Rossnagel said. “The problem with really cold temperatures is that you are restricted with the amount of outside air that you can bring in. Outside air is always much drier than the air in the storage, so if you can bring in outside air, that air is drier, and as you push that through the pile, you will dry down some of these wet spots.”
At the same time, he added, colder temperatures may translate to higher sugars and undesirably dark potatoes when fried.
“It’s a fine line between having your temperatures high enough so that they will process, but low enough so that they store,” he said.
The remaining winter will determine how much of the stored potato crop will make it to spring, Sawatzky said, although the province’s seed potato crop may have a better chance of surviving due to its cooler storage.