What kind of rice should I use for growing oyster mushrooms or making grain spawn? – The Mushroom Conservatory (2024)

The most common question that I get about growing oyster mushrooms is “what kind of rice should I use for growing oyster mushrooms?” Hopefully, this will help demystify things a bit!

So… What kind of rice should I use for growing oyster mushrooms?

If you are using precooked “ready” rice – this is a great way to get your oyster mushrooms growing with zero prep work and minimal risk of contamination, I recommend it for beginning mushroom growers because it makes things a bit easier. When I say precooked rice, I mean the packs of whole grain brown rice that is already cooked and vacuum sealed into a plastic envelope with the intent that the end user microwaves the bag and eats the rice out of the bag during what I would assume is a fairly mundane lunch break. I love brown rice, plain rice out of a bag for lunch isn’t my forte. BUT it’s dynamite for growing mushrooms on. You’ll want to look for Ben’s Original Wholegrain Brown Ready Rice – here’s a picture of the bag you’re after, it’s usually $2 to $3. Store brand is fine as long as there isn’t a bunch of extra sodium added (Ben’s Original has about 7g, you don’t want more than that as sodium will inhibit fungal growth.)

How to prepare your own bags of brown rice for growing oyster mushrooms!

If you’d like to use regular brown rice and cook it yourself, congratulations! You’ll save a bunch of money and be able to grow a whole lot of mushrooms. You’ll want to cook the rice per the instructions on the bag, using about 25% less of the recommended amount of water, and cook for a few minutes less. You want it mostly cooked but still firm and dry-ish. While it’s still hot (just cool enough not to melt the bag) put it in a freezer zip bag, squeeze out the excess air and zip it shut. Once it’s cool, you can proceed per the instructions to inoculate your rice with the oyster mushroom liquid culture from your kit. You can do bags up to a gallon in size this way quite successfully, and you can grow directly from the colonized bag or use it as grain spawn for straw buckets, bags, or outdoor mushroom growing beds.

Can I use white rice for growing oyster mushrooms or making grain spawn?

You could technically use white rice to grow your oyster mushrooms on, but the trouble is that mycelium is white, and therefore it’s really hard to see if white mycelium has grown on white rice. Brown rice gives your mycelium a tiny bit more nutrition, and it’s way easier to see mycelium growing, so that’s why we recommend it. You can also use a bunch of other interesting grains like popcorn, birdseed and rye berries. For getting started though, you really can’t beat wholegrain brown rice.