UNCO Industries was founded in 1976 in Union Grove, Wisconsin with a simple belief: the best fertilizer on earth isn't made in a chemical plant — it's made by earthworms.

For over 45 years we've been perfecting the science of vermiculture, producing 100% pure earthworm castings under the Wiggle Worm brand. Today Wiggle Worm is one of the most trusted worm castings brands in the country, sold at Walmart and Amazon, and used by home gardeners, commercial farmers, and everyone in between.

What makes Wiggle Worm different is what we don't add. No fillers. No uneaten bedding material. No synthetic additives. Just pure, OMRI listed earthworm castings produced the way nature intended — by worms, in Wisconsin.

Our facility in Union Grove produces castings year-round, feeding our worms a carefully selected organic diet that results in nutrient-dense castings packed with beneficial microbes, humic acid, and water-soluble nutrients your plants can absorb immediately.

We're proud to be American-made, organically certified, and family-operated. Whether you're growing tomatoes in a raised bed or managing a commercial farm, Wiggle Worm castings are the same product — pure, consistent, and proven over 45 years.