Monday 29 March 2010

Growing your own mushrooms

We tend to think of the natural world as consisting of plants and animals, part of a life cycle dimly remembered from old textbooks: one inhaling oxygen and the other exhaling it, one creating food and the other eating it. But there is a third partner at least as vital, without which the other two could hardly survive, repairing the world quietly from under our feet.

The ground you walk on is actually woven like a mattress, infused with millions of tiny threads of fungi -- eating wood, dead matter and even rock and turning it back into plant food again. We only notice them when it comes time for them to reproduce, and their “fruit,” sticking out of the ground, are mushrooms.

Some fungi forge an alliance with the aboveground trees, living on their roots and absorbing the nutrients they need. Others prey on tiny animals, luring them into traps and consuming them. In humid areas they form nets like spider webs, catching leaves before they hit the ground. They include the largest and oldest organisms on earth – one in Oregon covers 2,200 acres of land and is thousands of years old, but you can walk around on it and see nothing.

According to mycologist – mushroom scientist – Paul Stamets, mushrooms were the first living things on land, breaking down rocks like lichens do today and making way for plants – and after extinctions like the meteor that killed off the dinosaurs, “mushrooms inherited the Earth.” In his astonishing TED talk, “Six Ways Mushrooms Can Save the World,” Stamets also describes how mushrooms can be used to fight invasive insects, create cures for various diseases, create ethanol for fuel, clean up toxic waste sites and rebuild sterile land.

Mushrooms grow in most parts of the world, so people everywhere have harvested them for food, with knowledge passed through the generations: which ones are poisonous, where they can be found and in what seasons.

Our ancestors probably ate mushrooms extensively, and may have had far more of them. Most of the forests we see today are second- or third-generation after being clear-cut, and many of the “old-growth” forests are managed, their dead wood cleared from the forest floor. In the time of early humans, of course, old-growth forests stretched from Ireland to Japan and across the Americas, their trees sustaining many generations of fungi even before they fell.

Mushrooms add minerals to the diet and flavour to meals, and can be roasted, boiled in soups, sautéed, pickled or dried. We are not experienced in harvesting wild mushrooms and will not do so without being certain of their safety, but there are many other ways to gather them without buying the individual plastic packages at the supermarket.

Our family bought a giant box of mushrooms at a reduced price the last couple of autumns, when mushrooms are most common. Then we dried them and saved them through the year, using them again and again in soups and stews.

If you have a mushroom farm nearby, you can ask for some of the spent soil for your garden –it is often not completely spent, and yields some mushrooms along with your garden plants. Even if it does not, it is extremely fertile.

You can also order packets of mycelium – the fungi that yields mushrooms –to grow your own mushroom logs. We had oaken logs from a tree we had to cut down, and ordered three varieties – shiitake, oyster and lion’s mane – to implant in them.
The mycelium came to us through the post, three packets with several bullets of fungi in each. The first step for us was drilling holes in each log, a few inches apart. Then we had to hammer the mycelium bullets into the holes – hard enough to get them firmly inside the wood without smashing them.

Finally, the packets came with a block of wax and a wire daub – a short stick with a cotton ball at the end, like a Q-tip – to seal the mycelium in the holes. We had to melt the wax in a pot and carry it outside to the logs, and rush to dab the wax on the mycelium before it hardens. Fungi need the wood to be somewhat wet to grow, but if the mycelium is bathed in water too quickly, the spores may wash away before they can take hold.

Finally, the logs must be soaked in water for a few weeks so the fungi can more easily munch on them. I dug a trench behind the shed, about two metres across and 50 centimetres deep. I lined the trench with plastic, dragged the oak logs across the property to the trench, dropped the logs in the trench and filled it with water. Once the logs have soaked for a month or so we can lay them to one side and come back later.

It will take anything from six to eighteen months for us to get mushrooms out of this, and of course there is a chance they may never come at all – it is an experiment that demands some patience. On the other hand, it required only an afternoon of work, and if successful will yield home-grown mushrooms for years to come.

Photos: Won't upload for some reason. See them at Energy Bulletin.


Erin Martineau said...

I got to see Stamets talk at the New England Organic Farming Association (NOFA) conference last summer, and once we got back to the farm, we immediately ordered six bags of myceliated spawn and created a couple big mushroom beds in our biggest gardens. While we hope to see some mushrooms coming around in the next six months, we were also hoping to introduce more mycelia into the garden soil, to break down minerals and nutrients and support plant growth. We'll see what happens!

He was an inspiring speaker, and his book, Mycelium Running, is a good overview of the amazing potential of mushrooms, both in your garden and for the Earth.

Brian Kaller said...


I envy you for seeing Stamets talk in person. How big were the bags, and what kind of soil did you have to put them in?