“Oyster Mushroom (Pleurotus ostreatus)” by Martin Cooper Ipswich is marked with CC BY 2.0. To view the terms, visit https://creativecommons.org/licenses/by/2.0/?ref=openverse

Let’s talk about mushrooms.

I’ve been comparing their underground stealthiness to Russian democracy, describing how they grow out of sight, keeping their peace until the right moment. I’ve pointed out that you never do know when they’re going to burst into the light and turn the world upside down.

But this week I want to stop with the metaphors and talk about actual mushrooms and how we might come to welcome them into our cities. I want to go beyond the pie-in-the-sky dreams of growing salads in our skyscrapers that some urban ecologists have proposed. No, I want to propose a much more, ok, underground idea that is no less soaring in its ambitions.

I want us all to start mushroom farms in our closets.

To be fair, I’ve tried and failed at mushroom farming before. As someone who is always looking for new ways of expanding the output of my Ground Zero Garden, mushrooms have forever been the next thing I’ll try. Oyster mushrooms grow well in used coffee grounds and I’ve often thought that I could rescue the spent grounds from coffee shops in my neighborhood and coax them to bear new life. In pursuit of this vision, I gathered a month’s worth of grounds, ordered some spores, and followed the steps laid out online: sterilize, contain, inoculate. I sat back and perused recipes for the mushroom risotto I expected to enjoy in the coming days.

It would require roughly 1.5 million square feet to grow every mushroom consumed in the city. That’s about 50% of the Empire State Building. Not entirely unattainable.

I was unsure how exactly I would know if it was working. I waited. I examined my bags of grounds. I hoped for the famous bursting forth phenomena that mushroom growers brag about. But it never happened. Just a bluish mold. And then…nothing.

What was I doing wrong? It seemed odd that an organism capable of growing at random on a fallen log in the woods or from a moist crack in the bathroom floor could elude me in such a precisely monitored environment.

What I needed was a mushroom therapist. And very soon, I found one.

In 500 square feet of a warehouse in Queens, Adam Norven operates Mushroom Queens. Norven quit his job as a lawyer a few years ago to pursue fungus full-time. Together with his brother, Norven has quickly expanded — increasing from three varieties to eight, and from one farmers’ market to six in just three years. All this while a pandemic raged. And with mushroom popularity on the rise, at least according to the New York Times’ 2022 food forecast, their future looks bright (or rather damp and dark, for optimal growing conditions).

I asked Norven to share tips on his process and learned that mushrooms are grown, commercially, in a sterile substrate that can consist of different media. Wood shavings, cardboard, and yes, coffee grounds, will all work. But you also need a supplemental material (straw, soybean hulls, wheat bran) to round out the mix. So I wasn’t entirely off course in my first run, I just needed to mix in some straw. Not sure I’ll be finding that for free on Broadway, though. If you can get the substrate right, the yields can be eye-popping: a healthy crop of mushrooms can grow to maturity in a matter of days, in relatively small spaces, off of recycled materials.

Turns out my experiment had succumbed to a notorious threat: contamination. Norven explained that other fungi or bacteria are the enemy of the homegrown crop. It is more than a bit ironic that these typically ubiquitous organisms, when cultivated, require sterility.

But all this can be overcome with the right techniques and careful husbandry. We could be growing mushrooms in the nooks and crannies of our high-rise apartments. We could cultivate an above-ground network of mycelium, a modern tin-can-and-string web composed of enthusiasts, experts, and their experiments.

And then Norven threw out an even more intriguing idea. What if we reclaimed all of our city’s underground spaces–abandoned train stations, underutilized subway rooms, crawl spaces, unused ducts, and the interstices between all our infrastructure. What if the farm we need to feed the city is right beneath our feet?

How much space are we talking about to keep the Big Apple flush in fungus? Americans consume about 4 pounds of fresh mushrooms on average each year. For New York City, that means about 34 million pounds. A back-of-the-envelope calculation based on Norven’s current yield of 10 thousand pounds from a 500 square foot room, means we’ll need roughly 1.5 million square feet to grow all the mushrooms New Yorkers consume. That’s about 50% of the Empire State Building. A lot, but not entirely unattainable.

Which is why this spring I’m starting a mushroom farm in my closet. With the right advice, the right substrate, and, yes, a modicum of sterility, I just might be able to contribute a few square feet to the self-sufficiency of the city I love.