Lawn, Landscape, Garden, Medicinal Plants

Do you look forward to a piping cup of hot coffee every morning to kickstart your day? Without a doubt, the caffeine laden brew is a favorite beverage in the United States. However, did you know that you can successfully use the leftover grounds as a grow medium? Whether you want to grow mushrooms indoors during the winter months or you just have limited cultivation space, you can successfully grow the tasty fungi in coffee grounds.

Growing Mushrooms in a Coffee Ground Mixture

Take freshly ground coffee grounds and mix a tiny amount of boiled straw (which acts as a substrate). The eco-friendly mixture is a great way to repurpose leftover grounds. Ideally, it should be made up of 70 percent coffee grounds with 20 percent straw. You can then mix in about 10 percent mushroom spawns for growth success.
If you want to be very precise then use a scale to weigh everything such as:

Five pounds of coffee grounds mixed with one pound of straw. Then use half a pound of mushroom spawns.

Supplies You’ll Need Lawn, Landscape, Garden, Medicinal Plants

  • Straw – pick pre-cut straw that measures about four inches long
  • Oyster mushroom spawns. You can buy these titbits online or purchase them
  • from mushroom producers. Never harvest from the wild. Store the
  • mushroom spans in the fridge until time to plant.
  • Freshly ground coffee grounds (used coffee grounds are necessary to prevent
  • unwanted mold growth)
  • Pot
  • Isopropyl alcohol
  • Plastic bags such as clear food storage bags or garbage bags
  • Twist ties
  • Thermometer
  • Salad spinner
  • Strainer
  • Utility knife such as an Exacto
  • Spray bottle

How to Grow Mushrooms in Coffee Grounds: Step by Step
Lawn, Landscape, Garden, Medicinal Plants

Below is a step-by-step guide that outlines how to grow mushrooms in coffee grounds:

  1. Wipe down everything using rubbing alcohol to clean and sterilize. Basically, disinfecting everything helps prevent the spread of unwanted and, often harmful bacteria, which is extremely important when cultivating mushrooms.
  2. Prior to mixing all of your ingredients together you are going to want to pasteurize your straw. To do this, bring a large pot of water to a boil and then submerge the straw. Maintain the straw at a consistent 170 degrees Fahrenheit for at least an hour and fifteen minutes. For this process, you are going to want to be precise so be sure to use your thermometer to determine that the water is a consistent temperature to sterilize the straw nicely.
  3. Strain all of the water from the straw by placing the straw in your salad strainer. Then put the straw directly into the salad spinner to pull all of the excess water out. You don’t want your straw weighed down by too much moisture.
  4. Mix the coffee grounds with the straw in a container. Break apart any large clumps of coffee grounds. You want it to be loose and free from clumps. You can use your hands or utensils to mix and chip the grounds.
  5. Use only freshly brewed coffee grounds to prevent unwanted mold growth.
  6. Examine your mushroom spawns and break any clumps apart gently with your hands.
  7. Place the mushroom spawns into the coffee ground potting mixture. Place everything in a plastic bag that has been wiped down with alcohol for sanitation.
  8. Seal the plastic bag tightly using a twist tie ( you can also use an elastic/rubber band if you do not have a twist tie). Prior to fastening the bag closed tightly, squeeze the air from the bag.
  9. Turn the bag upside down. Take your knife and make two to three holes in the plastic that measure about half an inch in diameter. Do not make the holes too big. You’ll also need to poke two smaller holes on the front of the bag and two additional smaller holes on the rear of the bag.
  10. Place the bag in a dark place. The temperature should hover at 65 to 75 degrees Fahrenheit. It should also not be overly humid. Keep the bag in the location for two to three weeks. Check on the bag periodically to determine if mycelium growth has started. The Mycelium growth cycle is the vegetative part of the fungi. It is similar to a root or stem. One major clue that the growth has started in the bag is the presence of a fluffy white substance which is the mycelium growth. Soon you’ll have baby mushrooms as the growth continues.
  11. Once the mycelium has taken off then you’ll probably notice tiny pinhead mushrooms. This process usually takes two to three weeks. Once the pinheads start to develop it’s time to make your holes bigger. Enlarge the holes to about two inches.
  12. Place your bag in a light area that features indirect light. A windowsill will suffice. You can now start spraying the bags with water. Spray the bags in the morning and in the evening. Once you notice the tops of the caps have started to flatten then it is time to harvest your mushrooms. This final process typically takes ten days.

Growing mushrooms coffee grounds is wonderfully rewarding and extremely easy. You can grow the tasty morsels all year long indoors for an endless bountiful harvest. Mushrooms are a great thing to cultivate with children because they are easy to grow, do not take exceedingly long, render a massive harvest, and when done correctly will always grow. Many people even grow mushrooms as a source of income. They can sell the mushrooms to local restaurants or at farmer’s markets for extra cash.

One More Method of Growing Mushrooms in Coffee Grounds

Another method of growing mushrooms in coffee grounds involves using a plastic container, coffee grounds, and cardboard. You layer the cardboard with the coffee ground and mushroom spawns in the plastic container. Place the container in a saucer and then drape a plastic bag over the top. Place the container in the dark and wait for growth – which takes about two weeks to start. You’ll want to keep the interior of the bag moist by spraying water once a day. Once the baby mushrooms start to grow it is time to move them into direct light to encourage growth.
Growing mushrooms in coffee grounds is remarkably easy and rewarding. You can also feel good about the sustainable, eco-friendly process.