Don’t Blindly Trust Manure, Hay, or Compost!

Reader Contribution by David Goodman
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There’s a huge problem destroying gardens in the US.

For those that aren’t familiar with the very high risk associated with putting manure or purchased compost in your gardens, you NEED to read this post. If you read me here or at, you may have heard me tell this story before—but I’m telling it again because it needs to be told. I don’t want anyone to make the same mistake I made.

About five years ago, I dropped a load of cow manure onto my property and promptly spread it around many of my fruit trees and berry bushes and through my garden beds. Within a couple of weeks, the plants were twisting into obscene fractals. Eventually, most of them died. It took me a while to figure out what was going on and when I did pin it down, I’d already lost about $1000 worth of plants. Mulberry trees were stunted, blackberries were killed, tomatoes were wrecked… it was a mess.

Danger of Toxic Aminopyralid in Soil Amendments

The culprit was “aminopyralid,” a toxin contained in the very popular herbicide Grazon(TM). I’ve since discovered that Grazon is everywhere in commercial agriculture now—and gardeners are losing their gardens right and left. Grazon is a “selective” herbicide. It kills broad-leafed plants… but it doesn’t kill grasses. Hay farmers love it for that reason—but gardeners are paying a steep price.

I was devastated after losing my gardens so I started sharing my story far and wide – including in Mother Earth News. Since I warned gardeners about this persistent herbicide, I’ve heard many, many stories – and I’ve been sent multiple heart-wrenching pictures of destroyed plants.

This stuff is in hay, in straw, in cow manure, horse manure, goat manure and who knows where else. It’s not destroyed in a compost heap and it passes right through an animal’s digestive tract and into your garden fully capable of killing your carefully tended beds for years. Years!

Here’s an example: I visited a homestead in Central Florida last year and saw the homeowner had piled composted horse manure into his garden beds. As soon as I saw all that manure, my heart sank and I dreaded what I might find on further inspection. Sure enough, all was not well. The newest growth on the tomato plants was twisting into thick coils that would never bear a single fruit—and the poor gardener who had added the manure to his beds had no idea what was going on. There’s nothing worse than poisoning your gardens while trying to feed them! Manure has been a gardeners’ best friend for time immemorial… but now it comes with huge risks.

I’d love to say there are still plenty of sources for safe manure or commercial compost, but there aren’t. At this point, I’ve seen so many wrecked gardens and heard so many mournful tales that I don’t trust any purchased manure or compost in the states. Let’s say you find a manure supply on a local farm. The homeowner tells you they “never spray their fields with anything.” That’s a start — but what about the hay they bring in to feed the animals during the winter? Is that all safe? Chances are it isn’t.

Is Purchased Compost Safe?

And what about purchasing compost? A lot of that compost contains materials that may be contaminated with aminopyralid or other herbicides. If an animal eats hay that was grown in a sprayed field, its manure will hurt your gardens — and most hay fields are being sprayed. That also means if you sweep up the hay from your local feed story to throw into your compost piles, you run a terrible risk.

Aminopyralid stays in the soil for a long time, too. Estimates range from 2 to 5+ years. The poison is taken up into the grass and passes through the animal’s digestive systems without losing its plant-killing power. If you add straw or hay to your gardens or compost pile, it can kill your plants. If you add manure, it can kill your plants. If you add compost from off-site that contained manure or any plant material contaminated with aminopyralids, it can kill your plants.

Compost Everything Right

As I wrote in my book Compost Everything: The Good Guide to Extreme Composting:

“Don’t bring manure, compost, straw, or grass clippings onto your property. Trust no one except people that don’t feed their animals any purchased hay and who you are sure do not spray their fields with anything. This is the only way to be completely sure your garden won’t get whacked!”

I stand by that statement. Just this spring a gardening group I’m involved with had multiple cases of poisoned gardens thanks to some compost-enriched soil with herbicide contamination they bought from a local supplier. Once this stuff gets in the supply line, it ends up everywhere.

Watch your backs, folks — I really want your gardens to succeed. What a shame that some of the very best organic amendments you can buy – manure and compost – are now a high-risk addition to your gardens. I’m seeing more and more people post about this problem and it’s very good to observe other gardeners take up the warning.

I lost my shirt (or at least a bunch of my plants) — you don’t have to lose yours, too. Learn to compost everything you can to avoid potentially contaminated outside amendments and stay safe out there.

David Goodman (David The Good) is a gardening expert and the author of five books available on Amazon, including Compost Everything: The Good Guide to Extreme Composting, Totally Crazy Easy Florida Gardening, Push the Zone: The Good Guide to Growing Tropical Plants Outside the Tropics and Grow or Die: The Good Guide to Survival Gardening. Find new inspiration every day at his popular gardening website. Read all of David’s MOTHER EARTH NEWS posts here.

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