It's time to make fungus the gardener's friend
“Alice remained looking thoughtfully at the mushroom for a minute, trying to make out which were the two sides of it; and as it was perfectly round, she found this a very difficult question.”
— Lewis Carroll, “Alice’s Adventures in Wonderland,” 1865
Lewis Carroll may have been describing the round-topped, spotted mushroom fly agaric in this passage from Chapter 5, which has Alice nibbling her way all around the mushroom in question — she shrinks when she eats from one side of it and grows when she eats from the other.
Fly agaric (Amanita muscaria) has hallucinogenic effects, one of which is making objects appear smaller and larger. This has led people to wonder how the author knew so much about the mushroom.
I wonder if Carroll knew mushrooms are the fruit of fungi that bear spores for reproduction, but the most magical feature of fungi occurs in the soil.
It’s there that the vegetative part of a fungus, composed of whitish-colored mycelium, grows long filaments that can extend for miles underground. Mycelium’s mass network of threads, called hyphae, feed soil microorganisms and attach themselves to plant roots. The hyphae become an extension of the plant’s root system, providing more access to nutrients and moisture in the soil.
Therefore, fungi are friends to the soil and the plants in our garden. It’s time for fungi to be the gardener’s friends, too.
For too long, fungus has been a dirty word for gardeners, something we want to keep away from our plants. The reason for the bad reputation is that some kinds of fungi are parasitic; they invade living plant tissue and feed on it, causing loathsome diseases such as downy mildew, anthracnose, rust, verticillium wilt, leaf spot and others.
However, there are more than five million known species of fungi, and most of them are saprophytes, meaning they feed on dead organic matter in the soil, which helps decomposition, and they form a symbiotic relationship with plants. The plants rely on mycorrhizal fungi (myco = fungus; rhiza = root) in order to absorb adequate amounts of nutrients and moisture from the soil, and the fungi need plants to supply them with carbohydrates for energy to do all of their marvelous work (similar to the way humans need plants).
It’s a mutually satisfying relationship that has developed over hundreds of millions of years. In fact, the affiliation is so beneficial that 95% of the world’s plants, including almost all of the plants in our garden and landscape, have developed a mycorrhizal relationship with fungi. Curiously, members of the Brassica family, such as broccoli, cauliflower and cabbage, do not form this relationship with fungi.
It’s clear that our gardens need fungi for healthy soil and plants. The good news is that gardeners can support the friendship between mycorrhizal fungi and plants simply by adding organic matter to the soil. Composted leaves and other plant debris add beneficial fungi and bacteria. So do decomposing cover crops that are laid over the soil or gently worked into the top few inches.
Tilling the soil, on the other hand, literally breaks up the friendship between fungi and plants by tearing apart the strands of mycelium hyphae and disturbing soil microorganisms. Fungicides applied to the soil kill mycorrhizal fungi as well as pathogenic fungi, in the same way that insecticides do not discriminate between the “good guys” and “bad guys.”
A complementary practice that increases fungal activity and helps to create a balanced ecosystem in the garden is polyculture planting, which involves growing different kinds of vegetables, herbs and flowers together, or growing cover crops and vegetables in alternate rows. A forest garden, so named because the design mimics a woodland ecosystem, features a community of edible fruit and nut trees, berry bushes, perennial herbs and vegetables grown annually.
The appearance of mushrooms in the garden means magical things are happening in the soil because microbes and fungi are plentiful and active. Fungus helps make our garden a true wonderland.
Rhonda Nowak is a Rogue Valley gardener, teacher and writer. Email her at Rnowak39@gmail.com. For more about gardening, visit her blog at http://blogs.esouthernoregon.com/theliterarygardener/ and check out her podcasts and videos at https://mailtribune.com/podcasts/the-literary-gardener.