Oyster mushrooms are easy to grow (and easy to eat!). One of the easiest methods uses used coffee grounds as a medium.

Ingredients list
Mushroom spawn, a sawdust loaded with mycelia (the fungus’ root structure). Buy the spawn online and at some garden supply stores.

Coffee grounds must be fresh and plentiful – mushrooms must be planted within 24 hours of the coffee being brewed.

Find a cafe or restaurant that can give you the volume you need: 51/2 to 6 pounds of grounds for every 1 pound of spawn.

You’ll be reusing a resource they’d otherwise throw out.


Planting instructions
Mushrooms require sterile conditions. Before you plant, wash your lower arms and hands with anti-bacterial soap.

Also, use a clean, sterile container: a specialized filter patch grow bag; a large, sealable freezer bag; or a sterilized plastic bucket will work.

The bags and buckets will require holes for air circulation.

Fill the container with moist, spent coffee grounds.

Break up the mushroom spawn and mix it in with the grounds. Cover with cellophane.

Lighting conditions

Move the container to a dark, warm (64°-77°) spot.

Lightly spray the spawn with water each day to keep it moist.

Wait two to three weeks, checking the spawn for dark green or brown mold, which can ruin the colony and make you sick. Get rid of any mold!

When the grounds have turned white – this is the mycelia colonizing the coffee grounds – remove the cellophane and relocate the container to a bright area, but not in the direct sunlight.

Now mist the contents twice a day.

Explosive growth

Within a week, tiny mushrooms will start to sprout.

Continue misting them, and they will nearly double in size each day.

After a few days, when the mushrooms turn fleshy and the edges of the caps begin to turn up, it’s time to harvest.

Cut the mushrooms at the base of their stems, and they’re ready to use.

Once the mushrooms have stopped sprouting, plant the grounds outdoors under mulch or compost, and they may continue to produce.

Daunted? Buy a mushroom growing kit for your first foray into DIY mushroom-growing.

Locally, North Spore sells the kits.

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