Have you ever asked yourself: why are barns in Wisconsin painted red? Contrary to the myth that farms were painted red so that cows could find their way home, it turns out that this strategy is non-factual because cattle are colorblind to the colors red and green. It'll surprise many to hear that barns weren't even originally red.
When barns started to become popular, they were not painted at all. The early New England settlers didn't have extra money to use towards painting their barns. So, for a while, they remained unpainted.
Around the late 1700s, farmers began to take initiative to protect their barns. To shelter the barns from the harmful elements that would hurt the wood, they began experimenting with ways to make protective paint.
The recipe they used consisted of skimmed milk, lime, and red iron oxide. This ultimately created a decaying red color that quickly became popular among farmers as it was inexpensive and long-lasting. Red iron oxide was (and still is) a very plentiful and easy compound to acquire.
Farmers also noticed that the red paint made the barns warmer in the wintertime because the darker color absorbs the sun rays more than a lighter color, such as tan. This soon became an American tradition and barns all over the country are red because of its convenience and affordability.
[Source: Live Science]