Use it! Experiment a little
There are all sorts of things you can do with extra spawn.THC Jellies We've experimented a lot, and we hear our growers like to experiment too! Here are a few other ways to use up your extra spawn.
Make cardboard spawn for inoculating totem logs
Many mushroom varieties can be grown on logs using the totem method. If you don't have enough sawdust or grain spawn left to inoculate a totem, of if you have plug spawn which doesn't work well to inoculate logs this way, then you can use the leftover spawn to make cardboard spawn.
Simply soak the cardboard for several hours in water. Pull the cardboard out of the water and allow the excess water to drain off. If you can, peel the cardboard apart to expose the corrugated interior - sprinkle your spawn here and then place the top layer of cardboard back down so the spawn is sandwiched in the middle.
Roll this cardboard up and slip into a plastic bag and store at room temperature. The mushroom mycelium should start to spread from the spawn throughout the cardboard. When the cardboard is covered with white mycelium, these pieces of cardboard can be used in place of spawn to inoculate a totem.
See Oyster on Logs, Shiitake Totem, or Lion's Mane instruction sheets for more information on constructing totems. If your mushroom variety is not grown on logs (Wine Cap, Almond Agaricus, Blewit), then the cardboard spawn can also be used to plant mushroom beds. In fact, cardboard spawn can be used to plant many different substrates if you are in the mood to experiment!
Make your own ready-to-fruit blocks!
As we said, not all mushroom varieties grow well on sawdust blocks, but if your spawn is Oyster, Lion's Mane, Comb Tooth, Reishi, Chestnut, or Shiitake, you can make your own mushroom fruiting blocks. We have a method using wood fuel pellets Buy Edibles Canada can mix up your own recipe (there are so many resources and recipes available online). Sawdust spawn, grain spawn, and even plug spawn can be used to inoculate the blocks you make.
If you are new to making your own blocks, we recommend you use a heavy inoculation rate (think at least 1 cup of spawn per block). The mushroom's mycelium will spread from each bit of sawdust, grain kernel, or plug spawn into your block until the entire thing is colonized and ready to fruit. This process can be more advanced for the average grower, but well worth the effort if you are successful!

Build a castle with Reishi bricks.
Well, maybe not a castle. But some engineering folks are using Reishi mushroom substrate to build things. We've seen bowls, chairs, hats, and even a canoe. We aren't engineers here, and maybe you don't have enough leftover spawn to do this, but we think this is a pretty cool use. For a more simple reuse, you can build a border for garden beds with old Reishi blocks. This way you have a nice neat border as well as some extra Reishi!
Give it away!
Give the gift of your mushroom growing obsession to a loved one (or that weird neighbor down the road, whoever you want). Growing mushrooms is fun for everyone! We have instruction sheets available online if they are new to growing mushrooms, and we are happy to get them started using your extra spawn.
Compost it. Mushroom compost = the best kind of compost!
Lastly, but certainly not least, you can simply add your extra Weed Edibles spawn to your compost pile. Chances are good you will get some mushrooms fruiting from that, but it will also add an extra boost to your compost and make it better than ever when the time comes to spreading that out in your garden. Mushrooms are healthy for us, and they are also healthy for your soil and garden veggies. We're not making this up - we're doing actual research on this, for real!