A science textbook will tell you the intense energy surrounding a lightning bolt causes a reaction between oxygen and nitrogen in the atmosphere that results in rain depositing nitric acid on the soil, where it becomes a usable form of nitrogen fertilizer for plants.
On Twitter and in coffee shops, farmers sometimes give lightning credit for a field “greening up” after a thunderstorm, but is this actually the case? In theory, the science is valid, but can lightning really give a crop a meaningful in-season nitrogen boost?
“It’s a nice thought, but it’s like a bedtime story,” says John Heard, soil nutrient specialist with Manitoba Agriculture, below.
While there are estimates this atmospheric nitrogen fixation might be worth 10 lbs of N per acre annually, Heard says the credit for a field “greening up” after a thunderstorm should go to H2O, not N.
And with the associated risk of that H2O coming in frozen form, lightning probably shouldn’t be favoured as source of nitrogen.