Note: It’s extremely important to be sure about identification before eating any mushrooms.

At the beginning of 2023, while still in a winter-imposed gardening hiatus, I was reading in The Gardener magazine an article about growing edible mushrooms outdoors. The article included basic instructions for how to set up a mushroom bed and I knew I had to try it! 

After some reading online on methods and species, I ordered spawn for wine cap mushrooms, Stropharia rugosoannulata. Wine caps – also called garden giants, king stropharia, and godzilla mushroom – are native to North America and Europe. They’re considered easy to grow, they taste good, spores are available online, and they aren’t commonly available at grocery stores or markets. 

Setting up 

The preferred substrate material for the mycelium to grow in is fresh wood chips, preferably “soft hardwoods” such as Manitoba maple, cottonwood, willow, soft maple, or magnolia. In May 2023 Ottawa was hit by a derecho storm and a large number of trees were felled or damaged. The City of Ottawa made available piles of wood chips; this ended up being ideal timing for my mushroom bed set-up and I collected several binfuls. I soaked the wood chips and some organic straw overnight so they’d be moist for the mushroom spores. 

To provide the necessary shade, I made a brick addition to the shady side of a raised planter in my vegetable garden. Wet cardboard went in the bottom to suppress weeds, then I covered it with a layer of wet straw, about 2 inches deep. This was tamped down to reduce air pockets. The winecap spawn had arrived and was in the fridge until the bed was ready. I crumbled and sprinkled the sawdust/spawn mixture evenly over the straw then covered it with about 3 inches of wood chips. To make a second area, I repeated the straw, spawn, wood chip layers around the rhubarb plants in the raised planter; the large leaves would eventually provide adequate shade for the mushrooms. The total area covered by the mushroom spawn was about 9 square feet (I had ordered the smallest amount of spawn I could find). One last step was to cover everything with some shade cloth. 

Image: The completed mushroom beds. 

Maintenance months and harvesting 

The set-up was completed before the end of April; all I had to do was keep the wood chips watered (especially during the first few weeks) and watch and wait. Apparently, I could expect mushrooms to start popping up about six months later, in the fall. After about a month, I dug my fingers into the wood chips to look for signs of growth. I was very pleased to immediately find some white, threadlike mycelium on the wood chips. There was also mycelium visible right at the surface, wherever there was something solid sitting on the surface. 

Image: Mycelium uncovered at five weeks  

In mid-August I was caught completely by surprise to discover that there were mushrooms! Some of them were already quite large and had grown crumpled under the shade cover, but some were perfect for harvesting. 

Image: First mushrooms appeared in mid-August 

I excitedly collected our first mushrooms, and we started using them in the kitchen. I wasn’t sure if we were about to get a deluge, so I was vigilant and checked every day for new ones popping up. There didn’t seem to be more after that initial flush and I relaxed a bit. Next thing I knew, more were up and again some were already getting quite large. I started checking more regularly and by early-September had harvested about three flushes. 

Image: Wine caps picked at their peak 

Over several days at the end of September, there was another decent flush of growth. I was a bit disappointed not to be overrun, but the overall results of the mushroom experiment were satisfying nonetheless. The mycelium will over-winter and mushroom harvests should continue year after year as long as fresh wood chips are provided in the spring. 

Year Two, 2024 

I hadn’t planned to buy more spawn for 2024 because I wanted to see what would come from the overwintered mycelium, but in the end I did, also adding fresh wood chips and organic straw. The harvest was smaller this year, perhaps because of insufficient watering, as I was away for five weeks of the summer. We also had some tremendously hot days. I tried to make my mushroom patch more shaded than last year by doubling up the shade cover. 

During the summer months, the mushrooms seem to grow to full size practically overnight and one has to be quick to harvest them before they get too big or get too eaten by the competition. With the cool autumn days, however, I’ve found that they grow much more slowly and there are fewer slugs eating their way through the garden. 

Eating Wine Caps 

A lot of mushrooms are described as having a “nutty” flavour while many others are ascribed an “umami” taste; wine caps have both, and they cook up nicely. The caps should be checked carefully for hidden millipedes or sowbugs that will otherwise end up in your dinner. 

There have been no other mushroom species popping up in my mushroom patch, and I carefully checked the documented characteristics of wine caps and examined my mushrooms closely, even creating a spore print to make sure it was the right colour (purple-grey). 

 

Note: It’s extremely important to be sure about identification before eating any mushrooms. 

 

Text and photos by Tuula Talvila 

Mushie.li9z@ncf.ca 

Tuula is a long-time member of the Ottawa Horticultural Society and a new member of the COG OSO Steering Committee. 

References: 

Dubois, Laurent. (2023, Spring). Mushrooms: The forgotten “vegetable.” The Gardener, Volume 29 (Issue 1), pp. 53-59. 

 

Grow Mushrooms Canada. Growing Wine Cap Mushrooms https://growmushroomscanada.ca/learn-to-grow/growing-wine-caps/ 

 

Mr. Mercy’s Mushrooms. Welcome to the world of mushroom growing. https://www.mrmercysmushrooms.com/growing-mushrooms/growing-methods 

 

Sayner, Adam. How to Grow mushrooms outdoors with a mushroom bed. https://grocycle.com/how-to-grow-mushrooms-outdoors/ 

Magical Mushrooms – Growing this edible fungus outdoors