I have alkaline soil, pH of 7.7 - mushroom compost at $5 to $6 per bag was a disaster. My rose turned very chlorotic (pale, yellowish leaves). I had to replace the soil. It's good to get your soil tested professionally before any amendments.

Karl recommended EarthCo. at drgoodearth.com for $20 they test for organic matter, phosphorus, potassium, magnesium, calcium, and accurate pH for a cup of soil. The soil-test kits at HomeDepo, Menards, and Lowe's are worthless and gave false pH since they use a very tiny soil sample (a few teaspoons!)

For these reasons, I would not buy it. If I were given some free, I would test the pH before putting it in or on rose soil. If the pH were 6.8 or lower, I would use it like any other decayed organic matter.

We really have had no soil, just sticky clay. I have amended my entire garden with a combination of top soil and mushroom compost.

Mary, I thank you so much for this information.

I would love to know if these processes were used in top soil or other products that we think are natural in our gardens.

Sammy

I read the article. It makes some good points but also makes assumptions that are not universally true. He compares shroom compost unfavorably to peat moss and to straw - are you kidding me??? Peat moss and straw have no nutritional content, which is what he disses shroom compost for. Peat moss is harvested unsustainably, through what amounts to strip mining or mountain top removal mining. And peat moss is bad for your soil here in the summer-dry Pacific Coast. It repels water in summer, and makes the soil waterlogged in the rainy winters. Straw? he can't be serious. Straw is a mulch, not a soil amendment.

Shroom compost has the advantage of being thoroughly decomposed organic matter, which is exactly what our soils need. Maybe in other places that's not so critical. Our soils are recently glaciated and have very little organic matter. My garden soil has only the organic matter that I add - when I did a particle analysis on moving in, there was no measurable organic matter.

His point about the pesticides used in mushroom production are good points if valid. (since his comparisons to peat moss and straw are not valid I have to question everything else too.) I've never asked the local company just what, how much, and how often they use pesticides. I'm not trying to be certified organic. But if I were, it would be good to know that mushroom compost may have pesticide residues. Keep in mind that these things do break down over time! especially in a high organic matter environment.

High pH, again, is not a problem in our area since our native soil is very acid. In alkaline areas people don't use things like cow manure due to pH problems, and cow manure tends to be a major ingredient in shroom compost.

Kayli, please note that the author of the article doesn't say that mushroom compost contains all these pesticides. All he says, is that commercial shroom producers are licensed to use them. He does not say that they do use them, or how much, or how often, or whether he's had shroom compost tested for residues, or anything. I do give him points for honesty but it requires a careful parsing of his text as he's really trying to persuade without out and out lying. His conclusions may be valid but he doesn't present data to allow us to draw our own conclusions.

In my area, roses and plants in general love mushroom compost. There's nothing in this article that persuades me not to use it as an amendment to add valuable, thoroughly composted, weed-free organic matter. In other areas, it would depend on the quality of the source and the characteristics of the native soil. I don't use it for winter protection as it is too soggy for our conditions. I've lost roses to canker when I've tried it that way. In colder drier winters it is probably fine.