The Secret Ingredient That Will Help You Grow Mushrooms At Home

Growing mushrooms is a wonderful way to cut back a little on your grocery bill, but they can be tricky to cultivate. If you're growing mushrooms at home, you need a substrate for them to sprout on, and a great one to try is coffee grounds. Gardeners are always looking for ways to turn their food waste into potential plant food, whether that's composting kitchen scraps or throwing random ingredients such as crushed egg shells into plant pots. If you've been struggling with what to do with your spent coffee grounds, then you'll be happy to hear that they're a great aid to mushroom growth. However, it doesn't work on all mushroom varieties — it's best for oyster mushrooms specifically. While there isn't any conclusive scientific evidence for this, the method is recommended by leading gardening and farming websites. Amateur urban farmers have also found anecdotal success with it, so it's worth a try if you're cultivating a new batch!

Coffee grounds, in particular, are a great fit for growing mushrooms because they provide an eco-friendly substrate. When choosing a substrate, you need to ensure it's pasteurized so there are no harmful bacteria or microbes that can either damage the growing shrooms or compete with them for nutrients. Since you pour boiling water over your grounds to brew your cup of Joe, your dregs are adequately pasteurized. Just make sure to use fresh grounds when doing this to ensure new bacteria or fungus doesn't grow. It's best to use them the day you brewed them.

How to use coffee grounds to grow mushrooms

First, allow your dregs to cool, and then mix them with your spawn in your growing container. You can either buy spawn from reputable sellers such as North Spore or simply use stems from oyster mushrooms you ate. If going the latter route, cut the stems in half to allow proper root growth. Mix the two ingredients together, and lightly cover your container with a cloth or plastic to keep it from drying out. Place it in a dark area, mist it daily to keep it hydrated, and you should start to see mycelium growth (the mushroom's roots) between 4 days to a week. If you'd like, you can continue to top off your container with fresh coffee grounds every time you brew them.

Once you see the mold-like mycelium take over the container (in about two to three weeks), cut holes into the lid, bag, or cloth that is covering your container. Oyster mushrooms need plenty of air circulation to grow, so it's important you don't skip this step. You also want to move it from the dark area and into one with indirect light. Give it about another week, and you should begin to see small pinheads growing. You can harvest them once they grow bigger and the heads turn flat.