As temperatures drop, overnight frost is becoming more common, but most farmers in northwest Iowa aren’t too worried about their crops. Many of the area’s corn crops have reached maturity and can handle short-term freezing without damage.
“Most of the corn in northwest Iowa is at physiological maturity, meaning it’s at the black layer stage where frost no longer poses a risk, explained Leah Ten Napel, a field agronomist with Iowa State University Extension. Most soybeans are mature too, but some that were planted late due to flooding could still be vulnerable to frost damage if they haven’t reached full maturity yet.
Farmers who experienced flooding and delayed their soybean planting have also opted for cover crops like oats and millets. However, there’s a risk for these crops if an early frost hits.
“If we get a frost early on, those crops could die, said Josh Rensink, co-owner of Pivotal Farm Services. “Farmers need to be mindful of the potential for nitrates in hay if they don’t harvest it in time.
Overall, the risk of frost isn’t a major concern for most farmers in the region.
If you have corn stalks that aren’t sturdy or are starting to weaken, frost might make things worse, causing more difficulty during harvest, Ten Napel noted.
Interestingly, some farmers are even looking forward to the frost.
It’s easier to work through a bean field after a frost because the plant is completely dead, Rensink added. Right now, the stems are still green, making it harder to get through the combine even though the beans are ready.
Experts advise waiting one to two weeks before harvesting crops that have been affected by frost.