I love oyster mushrooms! They have a texture half way between field mushrooms and shiitake mushrooms. Many people actually describe them as being “meaty.” They are incredibly simple to grow at home. I grow my oyster mushrooms in used coffee grinds! You’ll have to get hold of some spawn to begin with of course. But once you get going, you can keep propagating from there.
Oyster mushrooms can be grown on used coffee grinds, used teabags, dried straws, fresh-ish woodchips, stacks of newspapers or even old phone books. Basically anything woody in nature will do. Oyster mushrooms are not too picky about what they grow on, other types of mushrooms would have different requirements.
I ask the cafe downstairs of my office for a big bag of used coffee grinds whenever I want to propagate more of my mushrooms. This way I can be sure other mold hasn’t had a chance to set in and I can transfer my “mushroom mass” into the coffee grinds right away. If you want to collect your own used coffee grinds or teabags, freeze them as you go until you have about 3 liters.
Starting with 3 liters of coffee grinds, teabags, straws, wood chips, saw dust (not from treated timber), newspapers etc., put these into a plastic bag (I just use a relatively clean shopping bag) and add water to the bag to wet your mushroom growing material. Hold the bag shut and shake or knead the bag around to evenly wet your material. You want to have your material damp but not soggy. The bag shouldn’t drip and you certainly shouldn’t be able to squeeze out any water from the bag.
If you are using newly bought spawn, add a good handful to your material and shake and knead the bag again to mix. If you are propagating your old mushroom mass, add 2-3 handful of old mushroom mass to your new material and mix well.
Now tie up your plastic bag and more or less shape it into a log. Don’t fuss too much if your log doesn’t look like mine. Using scissors to cut 2cm crosses every 10cm apart around the “log”. Don’t cut on the top or bottom.
Fold a few sheets of newspapers roughly into the size of the bottom of your log and wet these. Put these into another plastic shopping bag and put your “log” on top of the damp newspapers and tie the outer plastic bag loosely.
Leave it alone for the mushroom to “infest” the new growing material. They like to grow between 10-20 C in a shady place. Don’t put them in a place that has total darkness. Keep checking every few days to make sure the newspapers at the bottom stays damp. Water the newspaper a little if it’s starting to dry out. Don’t water your log directly.
In a few weeks you’ll see what looks like white mold propagating through your material. Good news! Your mushrooms are establishing themselves. Once they take over the entire bag of growing material, they will begin to fruit – it is the fruit of mushrooms that we actually eat.
At first, mushroom fruits will pop out like tiny buttons from your cut crosses. Loosen your outer plastic bad a little to let the mushrooms breathe. Keep checking on them everyday because you will be able to harvest in 1-2 days. Once most of them start to flatten out, harvest all the mushrooms you can see because I find any small ones at this stage tends to shrivel rather than grow bigger.
Once you’ve had your first harvest from a bag, it’s the best time to propagate more! Just untie your “log”, take out 2-4 handful of this moldy “mushroom mass” to start a new log, tie the original log back and you can expect to have another 2 harvests out of it. The time it takes between harvests depends on the season and weather. Mine can take as long as 1.5 months in winter or as short as 2 weeks in summer.
I got my original spawn from here. If you live in New Zealand, you can find their growing kits in garden centers. If you live outside NZ, do a search online and I’m sure you will find a local supplier.
My favourite way to enjoy these is cooking them with some garlic and basil. You can check out my recipe here. Happy growing and eating! 🙂