If you’re anything like me, you do your  best to prevent fungi from growing,   like on your groceries or in your shower.

But a lot of people also like  shitakes and portabellos. And yes, those are fungal crops!

So sometimes the goal is  to encourage fungus growth. Despite how good we are at growing those fungi,   there are still some of them that  refuse to be produced on large scales. That’s why morels are such a forager’s dream: you can’t really plan out a  morel plot in your home garden.

They grow where they want to grow. But! After decades of research,   we’ve made a few breakthroughs in  cultivating the most stubborn fungi.

Here are four mushrooms we’ve  finally figured out how to farm. [♪ INTRO] First up, we have the mushroom  forager’s white whale: the morel. Specifically, black morels can  be found across North America,   and in a few other parts of the world. But for a long time, they had to be  foraged.

We couldn’t grow them ourselves. The primary roadblock was that morels  have super particular growing conditions. They seem to take their cues  from specific weather patterns,   like wet conditions following a period of nutrient  deprivation… aka spring rains after the winter!

And that’s why foragers also know  when to go looking for mushrooms. What kind of weather forecasts  mushrooms, if you will. While it’s tricky to create  those conditions artificially,   that hasn’t stopped folks from trying.

And researchers are making progress! A breakthrough came in 1986 when  researchers patented a process   for mimicking the weather patterns  of the morels’ natural life cycle. First, they fatten up the fungal network, called  mycelium, to get to a solid starting point.

Then they recreate winter conditions  by depriving it of nutrients for a   bit before “spring” kicks in  and they flood it with water. These external cues coax the mycelium  to “bloom” and produce mushrooms,   which spread spores and perpetuate the life cycle. So, after years of mystery, scientists finally  got a couple morels to grow in a greenhouse!

The next decades were spent perfecting this  method to produce morels on an industrial scale. And in China, black morels have  been cultivated en masse since 2012. But maybe that’s more by luck than skill…  It’s still quite common for crops to fail,   indicating there’s plenty left to learn.

Most recently, in 2022 a pair  of Danish farmers announced they   can use super precise climate control to  produce black morels indoors year round! As you can imagine, they’re still pretty  tightlipped about their morel-whispering skills. But one thing they’ve admitted is that growing   grass alongside the morels  seems to help them fruit.

Though maybe the best way to grow  morels is with complete nonchalance,   like when you're trying to  get a cat to let you pet it. Because morels commonly pop up  unplanned in suburban mulch! They most often pop up on the West Coast of  North America, but I found some once in Boston.

Maybe that load of mulch came from  Washington state or something. So you might not have to venture that  far to glimpse the rare and picky morel. The next mushroom on our list isn’t as picky  about weather in the same way as morels.

But it is picky about …corn. Huitlacoche could be seen as a brutal sign  of a ruined crop, or as a rare delicacy! This fungus forms when young ears of corn  are parasitized by a specific strain of smut.

Nope, not that kind of smut! We’re talking about fungal diseases. Far less sexy.

This kind of smut turns kernels into bulbous  tumors that are sometimes blue or black. So, not your typical sweet corn colors. Then they eventually burst open  to spread dusty, black spores.

Like a really gross confetti cannon. Basically the spores infiltrate the silk of  a young ear, spread through the plant tissue,   and secrete proteins that suppress the plant’s   immune system so it can hijack  the corn’s defense mechanisms. Talk about hardcore!

Now, I’m going to give it to you straight. This is bad for corn. Because it’s so detrimental to the  plant, researchers had to pick a side.

And for many years, they were  pro-corn, not pro-fungus. To prevent the smut from ruining crops,   farmers turned to fungus-resistant strains  of corn and relied heavily on fungicides. Under this antifungal  regime, huitlacoche was rare.

Which seems like a win! Except that it’s a delicacy in Mexican cuisine and  an important ingredient in indigenous medicine. There are 55 different diseases  that it’s used to treat!

So scientists had to figure out how to undo what  they’d done and find the ideal growing conditions. With a little bit of research,  we now know that corn strains   with higher sugar content are  the best hosts for huitlacoche. Now, Indigenous farmers have long  understood that young ears can be   inoculated with huitlacoche  spores via the corn silk.

But studies on the inoculation process have only  recently been published in peer-reviewed journals. Specifically, researchers have figured  out what age the corn should be when   it’s exposed to the fungus in order  to get maximum huitlacoche yield. And if the corn is kept unpollinated, they  can get up to 150% more huitlacoche from it!

With better understanding  of the fungus’s life cycle,   we know how to more successfully inoculate  corn and improve fungal crop yields. There have even been several successful  trials for greenhouse-cultivated huitlacoche. So if you hadn’t heard of it before, you might  be seeing a lot more of it in the future.

But you probably have heard of this next mushroom. It’s another legendary find for foragers  and Stardew Valley completionists. In the wild, chanterelles only grow  near the root systems of mature trees.

They need trees for their sugars. And in exchange, the fungi move water and  minerals from the soil toward the trees’ roots. But they aren’t usually too picky about the exact  trees they grow near, which helped researchers   understand the various weather and soil  conditions that typically produce fungal flushes.

The thing is, if you only grow next to  trees, you’re tough to grow in a greenhouse. Because, you know, trees are big. Despite that hangup, in the 1990s, they were  cultivated in greenhouses for the first time! …alongside seedlings of their symbiotic trees.

It took 16 months of patience  between inoculating the soil   and the first greenhouse chanterelle popping up. But even then, the research team  couldn’t tell what made it “bloom”. Part of the challenge is that chanterelles seem to  have a special relationship with certain bacteria.

Meaning you have to feed the mycelium,  the bacteria, and the host tree. But we’re still making progress  toward viable greenhouse production. Most recently, scientists have  unearthed a connection between   temperature fluctuations and a  subsequent flush of chanterelles: they, like me, prefer temperatures  between 19 and 27 degrees Celsius.

They’ve also learned chanterelles do best in  slightly acidic soil with a low nitrogen content. While these greenhouse studies are promising,   chanterelles still grow best in  forests alongside 10-40 year old trees. When they pop up naturally  in a young timber stand,   they can spread to establish  themselves throughout the forest.

But to speed things along, another strategy could  be to inoculate tree seedlings in a greenhouse,   then transplant them to the forest and  hope the mycelial network takes root. For forests that already produce chanterelles,  some groups are advocating for waiting longer   periods between timber cutting, which would allow  larger crops of chanterelles, year over year. There are also ongoing genetic studies,  which will hopefully reveal which chanterelle   species are best suited for cultivation in new  growth forests and greenhouses, respectively.

And since chanterelles aren’t the  only mushrooms that need trees,   all of this research could help us  grow porcini and matsutakes too! But arguably the most famous  tree-dependent fungus in the   culinary world gets its own section in this video. In general, mushrooms are the  fruiting body of a fungus.

The part capable of spreading spores. So if you see a mushroom above  ground, then you know that fungus   spreads its spores up here where wind  can carry them to a new destination. But unlike many other fungi, truffles’  fruiting bodies stay buried beneath the soil!

The truffles are the fruiting  body—the mushroom part. They rely on animals to eat the  mushroom and spread the spores that way. Because they grow entirely underground where we  can’t see them, it’s hard to study their growth.

And we can’t cultivate them in a lab,  which means we can’t study their growth… you get it, it’s a vicious cycle. But we do know a few things about them. We know that they only like  a couple types of host trees.

Black truffles, the most famous variety,  only grow near oak and hazelnut trees. But even if you plant those trees and  do your best to inoculate the soil… it still takes up to ten years to get your first  truffle crop … if you manage to get a crop at all. So truffle farming was slow going.

Until, a study in 2010 found that black  truffles have specific mating types! See, to successfully produce truffles,   you need both maternal and paternal genes  mixing it up in the same patch of soil. Any given patch of mycelium can produce  both maternal and paternal genes,   but they can’t fertilize themselves  the way some other fungi can.

Instead, they need another truffle patch  to contribute the opposite type of spores. If the first truffle patch  offers up maternal genes,   the second truffle patch needs  to put in paternal genes. And vice versa.

Or else, no next  generation of truffles from that lot. Insights like this help truffle farmers  increase their chances of bearing fruit. And that’s before we start branching  out to different kinds of truffles.

US-based farmers are also experimenting  with native truffle species, rather than   only pursuing the most famous European varieties. In the Pacific Northwest alone, there are  about 350 indigenous species of truffle! Maybe one of those could be  the next big culinary hit.

And native species could increase  a truffle farm’s biodiversity. Diversifying truffle varieties and  growing locations is a good idea anyway… Simulations of climate change trends  predict that there will soon be little   to no truffle-foraging grounds left in Europe. Heat, drought, fire, and pests could  realistically decimate up to 100% of   European truffle production  within the next 70 years.

But with this new truffle farming knowledge,   other countries could take on the mantle and  become the world’s next big truffle producer. Today, there are about 200  truffle farms across the US! Apparently, the secret to truffle farming  was in our own backyard all along.

As a mushroom enthusiast myself, I’m eager  to try some of these farmed fancy fungi. Maybe all I need to do is  buy a bag or two of mulch. [♪ OUTRO]