Coffee grounds make an excellent growing medium for certain tasty mushroom varieties. The spent grounds create ideal conditions for mushroom mycelium, the thread-like vegetative structure, to thrive. Plus as a bonus, mushrooms cultivated this way absorb the lingering coffee flavors! In this post we talk about Grow Mushrooms Coffee Grounds.
With just a few simple materials and following some basic mushroom growing principles, you can easily grow your own gourmet mushrooms fertilized by your used coffee grounds.
Why Coffee Grounds Work
Mushrooms naturally grow on decaying organic plant matter in nature. Coffee grounds essentially mimic this, providing nutrients as well as conditions mushrooms are accustomed to.
Grounds left over from brewing coffee are slightly acidic and retains some moisture, which mushrooms prefer. And as the grounds start decomposing, they release additional nutrients.
The carbon-rich grounds also provide plenty of food to feed helpful mycelium. Fungus mycelium exudes enzymes that break down the grounds further to unlock nutrients and stimulate growth.
Best Mushroom Varieties for Coffee
While many mushroom types can adapt to growing in spent coffee grounds supplemented with other nutrients, the easiest and tastiest varieties include:
– Oyster mushrooms – Fast-growing with mild flavor that pairs nicely with lingering coffee notes.
– Shimeji or Pioppino – Adds loamy flavors; the miniature brown caps are quite decorative.
– Lion’s mane – Distinctive shaggy white appearance; imparts rich, meaty flavor.
– Nameko – Appealing light orange coloration and supple texture when cooked.
Other manageable coffee-loving mushroom breeds include enoki, brown beech, king trumpet and some Shiitake strains. Avoid finicky mushrooms like button, portobello and most wild-sourced mycelium.
Preparing Used Coffee Grounds
You can collect used grounds fresh from your brewer, purchase some from a local coffee shop, or even use unused grounds near their expiration date. Store any excess in the freezer until needed.
Let fresh wet grounds dry out until they reach approximately 65% moisture content. Don’t let them dry out completely or over-compress. Next pasteurize the dry grounds by heating gently to 150-160°F for at least one hour, then let cool fully.
Pasteurization destroys harmful bacteria, clears petroleum residue and releases additional nutrients beneficial to mushrooms. Just avoid burning the grounds. After grounds are prepped, it’s time to inoculate!
Inoculating the Medium
In home mushroom growing, inoculation refers to introducing mushroom spawn into the growing medium in order to implant active mycelium. For coffee grounds, you can purchase mushroom spawn, usually sawdust permeated with desired mushroom mycelium strands. Or acquire a myceliated mushroom culture syringe.
To inoculate, simply inject sporulated mushroom spawn or liquid culture at regular intervals throughout prepared coffee grounds. Follow specific spacing patterns according to which mushrooms you’re cultivating. Gently mix spawn evenly throughout the bed about 2 inches deep.
Other layers like non-clumping cat litter or coconut coir can be added too, but coffee grounds will serve as the main nutrient source. Maintain proper moisture and steady temperatures around 70-75°F. Within a few weeks, mycelium should be fully established!
Fruiting Conditions
Once mycelium has had time to digest through the coffee medium and consolidate across all areas, it’s ready to start fruiting mushrooms. Expose the mycelium to proper humidity, fresh air exchange and lower light to coax mushrooms upward.
For small containers like 5-gallon buckets, you can create great fruiting conditions at home by simply covering with a clear plastic bag. Mist often with non-chlorinated water to maintain high humidity while allowing for some gaps in sealing to permit airflow.
Provide consistent diffuse lighting and maintain temperatures between 65-75°F. Avoid direct sunlight. Within just a week or less from introducing fruiting triggers, you should see mushroom growth begin!
Harvesting Your Mushrooms
It’s exciting to watch mushrooms bud, mature and expand over days. Exact growth rates depend on variables like moisture, air flow and strain traits. But once mushrooms stop enlarging, that signals peak harvesting time.
Use clean hands or small pruners to gently twist and pluck mushrooms at their base near the surface of the bed. Be selective and harvest in stages for full yields. Remove any unopened mushrooms and expired ones.
Some spent mushrooms may drop spores to continue re-colonizing the medium. Let mycelium regrow and produce additional small flushes. When mushroom production stalls, the old grounds make excellent garden compost!
Growing at a Larger Scale
The entire cultivation process can be scaled up well past small containers to accommodate larger yields. Intermediates can follow the same procedure but use larger bins, bags or beds approximately 3-12 inches deep filled with hydrated grounds mixed thoroughly with spawn.
Commercial operations dedicate entire climate-controlled mushroom houses where rows of inoculated coffee beds in tray stacks or bags undergo controlled fruiting periods in sequence for continual harvests. Advanced mechanics now even automate loading, moving and harvesting beds.
Additional Tips & Troubleshooting
– Disinfect tools and equipment; avoid cross-contamination between batches.
– Check moisture and humidity frequently; drier climates may require more misting.
– Allow light air circulation; alter plastic covering as needed.
– Monitor for molds and treat affected areas promptly.
– Refrigerate harvested mushrooms in breathable container for 1-2 weeks max.
Following the fundamentals for inoculating, maintaining and triggering your mycelium beds to produce mushrooms isn’t too difficult. Get in a routine of retrieving spent coffee grounds, expanding inoculated beds as available space permits, and harvesting fresh mushrooms for use in your favorite dishes.
The continuous breakdown action helps sustain your mini-mushroom farmstead. So kick back with your daily mug of coffee, confident that soon those discarded grounds will supply organic gourmet mushrooms bursting with enjoyable textures and coffee-accented flavors. I hope this Grow Mushrooms Coffee Grounds post helps you.