Growing Mushrooms in Coffee Grounds for the Coffee-Loving Households

Growing Mushrooms in Coffee Grounds for the Coffee-Loving Households

Growing mushrooms in coffee grounds is a popular method for small-scale cultivation at home, and you don’t even need to drink coffee to do it 

Growing mushrooms in coffee grounds in one method of mushroom cultivation that goes perfectly at home. At home, growing mushrooms in coffee grounds is among the easiest and cheapest growing methods that can be done. With a little guidance growing mushrooms in coffee grounds at home is very easy to do.

This article will guide you on how you can be growing your own mushrooms in coffee grounds with relative ease at your home. This method of growing mushroom makes use of the already available resources that are present within your household therefore making it an ideal growing technique for those living under a strict budget or who have limited access to mushroom growing kits and other such professional growing techniques like colonizing substrates, or using a flow hood to make sterile inoculations. Growing mushrooms in coffee grounds involves using the readily available material right from within your kitchen, which is spent coffee grounds that have already been used to make some delicious coffee.  

Here’s our description of growing mushrooms in coffee grounds with step-by-step instructions:

Step 1: Obtain the appropriate materials for growing mushrooms in coffee grounds

You will need the following materials for growing mushrooms in your coffee grounds at home; a steady supply of coffee grounds (make sure that you use fresh coffee grounds), a container to put the coffee grounds substrate in, and mushroom spawn of the desired mushroom species you want to grow. You can buy fully-colonized mushroom spawn from us, and we recommend using either the grain spawn or the sawdust spawn. 

The container could be a myriad of things. It could be a plastic bottle that you cut the top off and clean the inside. You could use filter patch bags if you have the opportunity to get them. You could also use 3-5 gallon buckets as well. 

Step 2: Prepare the substrate (aka the coffee grounds)

Having a household full of coffee drinkers makes this process of growing mushrooms in coffee grounds easier as you will need a good amount of spent coffee grounds. If you are not a big coffee drinker yourself, and you do not have access to a lot of coffee grounds, try visiting a local coffee shop. Many coffee shops offer their spent coffee grounds to interested parties free of charge, and you're likely doing them a favor by getting rid of the used coffee grounds for them. A busy coffee shop will probably be able to give you the amount you need within a day.

One note about using coffee grounds as your substrate: Freshly-used coffee grounds will be ready to use for your inoculation. You do not need to pasteurize the substrate since the brewing process already did that for you. 

Step 3: Mix your mushroom spawn with the spent coffee grounds

We recommend that you mix your spawn with your coffee grounds the same day that you get the used coffee grounds. Otherwise, you run the risk of the coffee grounds becoming contaminated, leading to a failed mushroom grow.

We recommend that you start by using a ratio of around 1:5, spawn to the substrate. 

Wash your hands and arms and dry them before beginning. Mix the mushroom spawn into the coffee grounds in a large clean bowl, and distribute it evenly throughout the spent coffee grounds. 

Step 4: Fill your containers with substrate and spawn

Fill your container with your mixture of spawn and substrate and seal it shut at the top. Place your filled bags or containers somewhere warm, around 65-70 degrees Fahrenheit. Be sure to keep it out of direct sunlight as well. Your mixture will turn a white color as the mycelium colonizes the substrate completely.

Step 5: Fruiting your mushrooms

Once the white mycelium has colonized your substrate, you can begin the fruiting process. If you use bags as a container, you can cut holes on the broad side of the bags and begin misting the area with water. Mushrooms like humid conditions, so make sure your mushrooms do not dry out. We recommend having a thermometer and hygrometer around if possible, so you can know exactly what the temperature and humidity levels are where your mushroom kits are located. Dialing in the ideal conditions will help your mushrooms get the biggest yield. 

Continue misting until you see the baby mushrooms beginning to pin. This will take up to a couple of weeks, depending on the species of mushroom you are growing. Some mushrooms can begin pinning within a few days of the misting process. 

We recommend growing blue oyster mushrooms on coffee grounds as these are a perfect option for beginning mushroom farmers. Plus the blue oysters will do really well on this substrate. The blue oysters will begin pinning within a week, and they will be ready to harvest after another 7-10 days, or once you notice the edge of the cap starting to turn upwards.

Have you tried growing mushrooms in coffee grounds? 

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