Written by Simon Hart
Simon has been gardening for over 40 years, including work in the 1980s with nutrient film technique and tissue culture. As a garden experimenter, Simon has taken various skills over the years and applied them to his plants, focusing on observation and soil health both indoors and out. Practical hands-on experience has been combined with post-secondary science-based agricultural programs, and in addition to sharing his knowledge with Garden Culture Magazine, Simon continues to guest lecture at local universities and other establishments on a variety of garden topics.
Follow Simon @BentleyGrove
It’s not something we think of that often unless, perhaps, you are Paul Stamets, but the mycelium superhighways under our feet are a critical part of our environment. There is growing evidence that fungi drive their environment, influencing what type of ecosystem builds and sustains above and around them.
Friendly Fungi
The main problem in taking advantage of this is the fact that fungi like a consistent, easy-going kind of environment, and humans, well, we create more dynamic circumstances. The way we farm and develop the land has had wide-ranging effects on fungal populations.
So how do we square these two ideas? Is there a way to improve the situation for fungi and take advantage of the enormous benefits of having them functioning in our soils? There are ways to reconnect with these fascinating organisms. The first thing to recognize is that fungi are looking for permanence. Most vegetable gardens lead to soil disturbance, so fungi are generally more suited for perennial systems. Enter the food forest – a masterfully intuitive design concept.
What Is A Food Forest?
A food forest is a type of permanent agricultural system that builds a 3-dimensional food-producing space by layering plants together, similar to what you would see in a natural environment. It all starts with an open canopy of well-placed trees up to 120 ft high, such as pecans in rural areas, or semi-dwarf pears in the city. Shorter trees and shrubs surrounded by perennials are sprinkled beneath them and enhanced further with vines, root crops, and ground cover. Food forest designs will generally focus on fruit, nuts, fiber, and timber. These types of gardens are slow to build compared to vegetable beds but are more permanent. Because the system is allowed to grow and thrive without much soil disturbance, fungi have a much better chance of flourishing. These fascinating garden dwellers need time to expand, but there are ways to improve their growth.
In Every Great Garden…
The key to a garden is good soil; the key to good soil is biology, and the key to biology is carbon. Many of us are familiar with feeding carbon to bacteria in the form of carbohydrates, like molasses, but fungi are slower and need different types. A wide range of options are available to the avid gardener:
- Compost – a standard bullet-proof soil amendment. Compost, worm castings, and insect frass can all provide biology and organic matter rich in carbon.
- Organic fertilizer – an organic fertiliser will also help with soil carbon levels.
- Humic acid – the remnants of decomposed plant material, this carbon source is the foundation of any soil system.
- Wood chips – make sure to age them to let biology start working before putting it into the soil. Wood chips are fantastic for fungi and will generally be full of mycelium in less than a year. They can be spread on the surface or worked into the soil.
- Biochar – persistent carbon that will not break down over time. If you can find it, biochar will outlast every tree in your garden, staying intact for hundreds of years. It’s like catnip for mycorrhizae.
- Coarse woody debris – any wood is good wood. If a neighbor is chopping down an old cherry tree, see if you can stick it in your garden. Did some big branches fall off a tree in your yard? Find a place to bury them in the garden. Wood will break down slowly and provide food and habitat for growing fungi for many years.
- Logs – if you have space and the resources, logs are nature’s nursery, not only supporting fungi but providing multiple benefits to your soil. Whether under the surface or laying on the ground, logs in the garden are second to none for habitat.
Recycling Carbon
I have been creating a food forest of my own for 13 years now, and I have used wood in several different ways to build fungi in my 3-acre sanctuary. I was lucky to have an actual forest in the place where I wanted to grow food. The unfortunate fact was that this meant cutting multiple 120 ft+ trees. The sadness of doing this was tempered by the idea of recycling this carbon into the growth of a new type of forest while keeping the remaining forest healthy. I have built habitat out of woodpiles and forest soil; I have buried logs under my pathways and raised beds; I have left logs and stumps exposed to act as nurse logs and have even started growing fruit directly in them; I chipped all the branches for wood chips to be top-dressed or mixed with soil.
There are now eight types of nuts and over 40 types of fruit growing in the forest, alongside more than 200 native plant species (existing and purchased). These are complemented by at least 26 types of fruiting fungi. The wood has done its job by building fungal mass, improving soil quality, and providing habitat for numerous forest-dwelling species beyond fungi, such as native bees. I even had an otter spend a few weeks in a woodpile near the creek one year!
You Can Do It!
It’s possible to have a garden that embraces fungi no matter where you live, but it involves being creative (no wood? Maybe straw can help), thinking about carbon (brown layer in a compost pile), and low impact gardening (sell the roto-tiller). Focus on perennial polyculture (lots of variety) and on a multi-story canopy (different types of plants that fit different niches), and the fungi will come naturally!