It is often said that the grass won't turn green until after the first thunderstorm of spring.

This old adage is based in truth… but it's not entirely accurate. It's called nitrogen fixation.

The air around us is 78 percent nitrogen, but it's an inert gas.

It pretty much means this nitrogen just takes up space.

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The electrical energy of a lightning strike is able to break the bonds of the nitrogen compound.

Nitrogen atoms then bond with oxygen to form nitrogen oxygen which dissolves in raindrops forming nitric acid.

Then, that forms nitrates, which become fertilizer for the grass and other plants.

But actually it's microorganisms in the soil that do most of the nitrogen fixation.

Lawns green up in spring because the soil warms up and we get enough rain to make the grassroots happy.

A lightning strike only adds a tiny bit of nitrogen.