How Do We Keep Wisconsin Potatoes Comfortable in Extreme Heat?
In some sense, potatoes are a bit like humans — the extreme daytime heat indices and hot nights of the past week make tubers (and us) very uncomfortable. Like people, potatoes also need activity (growth) during the day and rest at night.
Potatoes are a cool season crop. They don’t really grow when it’s over 85 degrees — they tend to rest. They also prefer fluctuating day and night temperatures and plenty of sunshine. So a sunny day with a high of 75 degrees and a low of 55 to 60 degrees is ideal — it allows plants to grow rapidly and recover during the cool evening.
Potatoes are also photoperiod sensitive. As the daylight hours become shorter they sense the need to grow their tubers more quickly — they “bulk up”. Farmers call it “finishing off”. Potatoes of the best quality usually grow at a continuous, steady pace.
So, how do we keep Wisconsin potatoes comfortable during a week of extreme heat and humidity? We keep their feet (roots and tubers) cool and wet. Ever turn on the sprinkler on a hot day to enjoy the cool air? We do the same for potatoes when it’s hot. Rain or irrigation water cools the soil and reduces the temperature as it evaporates and the wind moves the air around the plants.
The tricky part is monitoring how much moisture we provide. We have to carefully monitor how wet the crop gets because too much moisture can create the risk for spreading disease.
Yes, the extreme heat has been challenging. But our Wisconsin potato growers work to control what they can using tried-and-true best practices that interact positively with the environment. Keeping potatoes, like humans, well-hydrated.