Shiitake mushrooms are the yummiest variety, in my opinion. They’re also the most expensive in the shops, and virtually impossible to find in an organic variety (at least where we live). Solution: grow your own.
You’ll be happy to hear that making your own shiitake mushroom log turns out to be very easy. It would make a great holiday project for any family, or a great skill-share workshop in your community. Here’s how you do it.
We made our shiitake logs as part of a workshop we ran in Sydney recently…
Making a shiitake log: materials
The log: a freshly cut log is best, as this means other fungus haven’t yet had a chance to colonize it (and less competition means more shiitake mushrooms for you). ‘Fresh’ means cut in the last 72 hours or so. Apparently 100-150mm diameter is ideal, length preferably no less than 60 – 75cm.
You can use a variety of woods. We used eucalypt, and we de-barked them as they had thick, woody bark. If you log has thin bark, you wouldn’t need to do this.
The holes: we drilled each log with 20 holes, evenly spaced around the log, width 8.5mm if you’re using standard plug spawn – the diameter of the dowel plugs increases from swelling in the moist spawn environment.
If you’re using sawdust spawn, this might be different. You can get a small hand tool that injects a small chunk of sawdust spawn, for example, snugly into 12mm holes.
The spawn: The basic idea here is to fill the holes in the log with shiitake spawn (mycelium). Plug spawn (shiitake spawn that has colonized a wooden plug) is one way of doing this. Colonizing sawdust with shiitake spawn, and putting that in the holes, is another way. We used plug spawn.
Inoculating the log: This was the fun part. You take a spawn plug and tap it into the hole. Ta da! One innoculated log. Repeat until you run out of holes.
Sealing the log: this step is to ensure that you actually get a harvest of shiitakes, and not some other crazy fungi. To ensure that other fungi spores, which are always floating around in the air, don’t take over your carefully prepapred log and out-compete your shiitake spawn, you need to seal all open surfaces on the log.
The best way to seal the log is with beeswax, as it’s the most natural substance for the job. The mushrooms absorb whatever they come into contact with, so obviously you don’t want to use petroleum or artificially based waxes or sealants on your food.
In a perfect world you would use organic beeswax, as beeswax is a bio-accumulator for whatever toxins the bees have encountered (and most conventionally-managed bees encounter quite a bit, both in and out of the hive). If you can’t, just go with whatever beeswax you can get. It’s still the best option for this job.
So melt down some beeswax in a saucepan, and apply some anywhere the log has been penetrated. Don’t forget to seal each end of the log where it’s been cut, as well as each hole.
The knock-on effect: just before you site your log, give it a good bump and a whack. This stimulates the mycelium to proceed into a state which will result in a later ‘flush’ (blooming of mushrooms).
Which makes sense, when you think about it. This kind of mushroom grows on dead wood. Intrinsic to that wood becoming dead is it’s falling (a branch off a tree, or a trunk falling to the ground). In turn, this great big thump activates the mycelium. So you can simulate this by giving your log a thumping. Pretty cool, eh?
Siting your log: hurrah! Your log is now prepared. Now for the waiting bit. Take your log and put it somewhere with good airflow, preferably in semi-shade. Keeping it moist is good, but apparently the shiitake mushrooms will fruit even if the log is not constantly moist, it will just take longer. If you have a tree, put your log up in the branches, or close to the tree somehow. Make sure you keep it out of contact with the ground.
And in the space of 6-12 months, your log should look something like this:
Harvest: your log should yield 5-6 ‘flushes’ or harvests following its first. Enjoy.
We run Mushroom Cultivation courses! Mostly in Sydney, at this point. Check them out here…
Many thanks to Will Bowowski, Trev Bamford for the documentation and Cathy X for her photos.