The Soil Your Undies Challenge: A New Way to Build Better Soil

The Soil Your Undies Challenge: A New Way to Build Better Soil

In late 2018, a handful of Oregon farmers went out onto their land, dug a hole, and buried a new pair of cotton underwear.

The farmers call it the “Soil Your Undies” challenge. The idea is simple: if soil is healthy, the microbes it contains will dissolve a pair of underwear in about 60 days.

Soil microbes are constantly decomposing organic matter into nutrients that enrich the soil, creating an ideal environment for crops to grow.

Healthy soil is full of friendly microbes. If your soil is healthy, you should be able to bury a pair of cotton underwear, come back in two months, and dig up nothing but the elastic waistband (the microbes aren’t so keen on eating rubber, so the waistband stays behind).

The Soil Your Undies challenge is a simple way to test your land’s soil quality –– and most of the farmers have been happy with their results.


Corey Miller, a wheat farmer in northeastern Oregon, is experimenting with a new style of no-till farming. The idea is that if you balance the ecosystem on your farm and then leave your soil alone, the undisturbed soil microbes will have a chance to work their magic, creating more nutrient-dense soil with less work on the part of the farmer.

Corey wasn’t sure how well his new farming style was working –– until he dug up his undies and found that they were completely disintegrated, even though he’d had an unusually dry season. Now he’s sold on no-till farming. His wheat is healthy, his land is thriving, and he doesn’t have to spend his days churning up soil.


Now, in 2021, the challenge has begun spreading outside Oregon. Middle school students in Missouri and Tennessee buried underwear all across their counties and returned to find them in various stages of decomposition. They used the results to figure out which parts of the county had healthy soil and which ones needed a little help.

The Soil Your Undies challenge is open to everyone. It’s a fun way to learn about your yard’s soil quality and strengthen your local land, and it’s growing rapidly.

If you want to take part in the challenge, pick up a pair of new, 100% cotton underwear, grab a shovel (or a spoon –– that’s what the middle-schoolers used) and follow these simple instructions. Once you complete the challenge, you’ll get a photo and write-up on the USDA website, as well as a pin on the Soil Your Undies challenge tracker map.