Compost – White Roots Growing in It

Q: I am an experienced gardener and have a puzzling situation to which I cannot find the answer. Anytime I have a pile of compost or wood chips, a mass of string-like roots have grown in the bottom of the pile. They appear not to be alive, yet they continue to form clumps throughout the pile. If I use this stuff in my flower beds and come back a year later, the beds are matted and dry. I have tried placing plastic under my compost piles, however, the mass still forms near the bottom. Is there any answer to this problem?

A: I can’t resist the remark that fungi just want to have fun….and that is exactly what is happening in your compost. Fungi are at work decomposing organic matter. The threads you find are long, tiny tubes, called hyphae. They absorb and transport nutrients, protecting them from other organisms. A big clump of hyphae is called a mycelium.

As fungi do their work, they consume nitrogen. This might explain why your flowers do poorly after adding mycelium to the soil. You innoculate the soil around the flowers with a big mass of fungi and the fungi rob nutrients from the plants. Eventually the fungi will die and release their nutrients but your flowers will do poorly in the meantime.

The presence of fungus is not a bad thing. It is just part of the circle of nature. If you vigorously chop up the fungal mass before adding it to the flower bed I don’t think the hyphae would be organized enough to do any harm. You could also begin screening your compost before using it in the garden. Putting plastic on the bottom of the compost pile didn’t help because the fungi grew internally in the pile.