Photo by Guido Blokker on Unsplash.

OK, so they’re not plants but every good gardener knows that mycorrhizae, the thread-like fungi that lace our soil, are of our best friends for soil health and plant growth. With that in mind, here are a few recent stories about fungi and mushrooms.

Renato Tomassetti and Bella after she found a truffle. “Black gold,” Mr. Tomassetti said. Photo credit: Stephanie Gengotti for The New York Times

The Perils of Hunting for Truffles

Jason Horowitz, the New York Times’ Rome bureau chief writes about the highly competitive business of truffle-hunting in Italy. Competition is so cut-throat that some have taken to poisoning the dogs of known truffle hunters. Horowitz’s article focuses on 80-year-old Renato Tomassetti and his dog Bella, an energetic Lagotto Romagnolo, a stocky, curly-haired breed also known as  Italy’s “Truffle Dog”. The article is lushly illustrated with photos by Stepanie Gengotti.

Mushrooms can live without us, but we can’t live without them. (Photo: Zahra via Unsplash.

No fungi? No forests, no food, no future!

David Suzuki with contributions from senior editor and writer Ian Hanington writes about the importance of fungi to humans. Cheese, bread, wine, beer, kombucha and chocolate would not exist without fungi. It makes all these tasty items possible. In fact, almost all food production relies on fungi. Most plants need it to obtain nutrients and water. Trees and other plants in a forest connect through intricate fungal, or mycorrhizal, networks of tiny mycelium threads that transfer nutrients, water and information between them, and that facilitate decomposition, without which life couldn’t go on. All fermented foods — including beer, wine, chocolate, cheese, bread, soy sauce and tofu — require yeasts, a single-celled fungus. Fungi have also been indispensable in preserving foods. And cows and other ruminants need gut fungi to break down grass. This Guardian article reports that fungi are also responsible for many important medical breakthroughs and for a lot of carbon sequestration.

For such an important group of organisms, we know almost nothing about fungi. Until the 1970s, fungi were classified as plants. We now know they are closer to animals. “They’re really weird organisms with the most bizarre life cycle. And yet when you understand their role in the Earth’s ecosystem, you realise that they underpin life on Earth,” said Kathy Willis, director of science at the Royal Botanic Gardens, Kew, which leads “State of the World’s Plants and Fungi” assessments.

Photo by Irina Iriser on Pexels.

Growing Mushrooms without Pesticides

Ali Jones reports in Horizon, the EU research and innovation magazine, on how La Rioja in northern Spain is both a centre for mushroom growing and research into greener growing strategies. Growing mushrooms commercially requires managing humidity, temperature and light to produce a regular, quality crop while contending with pest control. For now, pest control means relying on pesticides, which are becoming expensive and, of course, have environmental risks. Pablo Martínez, an agronomist, was drawn to the specialist mushroom sector after a chance conversation with a former colleague. Based at the Mushroom Technological Research Centre of La Rioja (CTICH), Martínez manages a Europe-wide project to tackle the environmental challenges faced by the industry.

Mushrooms are grown on a substrate, or base layer, made of straw and animal manure, then covered with a thick blanket of peat known as the casing. Made up of partially decayed vegetation, peat perfectly mimics nature’s forest floors that so readily yield mushrooms. The depletion of precious finite peatlands is a global concern. These wetlands store more carbon than all other vegetation types in the world combined and their conservation is ever more important for countering climate change. “Mounting restrictions on peat extraction in European countries threaten the long-term continuity of peat supplies,” said Martínez. “We’re looking to develop a new product for growing mushrooms that could cut pesticide use by 90% while reducing the industry’s reliance on peat.” EU-funded research aims to to create a low-peat sustainable casing for cultivated mushrooms made from renewable materials sourced close to existing mushroom production. While the exact details are under wraps, it will combine with a substance known as a biostimulant to enhance the natural growing processes and strengthen the mushroom mycelium in their early phase, protecting them against disease without the need for chemical pesticides.

Meanwhile, in Norway, two mushroom enthusiasts have pioneered a project to explore whether the crop could be cultivated in food waste. The EU-funded initiative is called VegWaMus CirCrop.

The death cap mushroom (Amanita phalloides), a small, green-tinged mushroom, sprouting from a forest floor. (Image credit: Pierre/Alamy Stock Photo)

How the world’s deadliest mushroom conquered California

Writing in Live Science, Ben Turner reports on the spread of the aptly-named death cap mushroom. The poisonous “death cap” mushroom (Amanita phalloides) is an invasive fungus whose fatal amatoxin accounts for more than 90% of deaths from mushrooms worldwide, but how it spread from its European origins to colonize every continent except Antarctica has long been a mystery. Now, a study published to the preprint server biorXiv, has found a reason why: the California version of the death cap can fertilize itself and produce perfect copies, sidestepping the need to mate before wafting its spores over an unconquered region.

“The diverse reproductive strategies of invasive death caps are likely facilitating its rapid spread, revealing a profound similarity between plant, animal and fungal invasions,” the researchers wrote in the preprint.

Photo credit: Tim Sandall

Adding fungi makes rosemary tastier

Finally, research from the Royal Horticultural Society (RHS), Vitacress Herbs and Royal Holloway has shown that the addition of mycorrhizal fungi to soil leads to increased production of essential oils in rosemary, making the plants more aromatic and flavorsome. Adding mycorrhizal fungi did not affect the shape or structure of the plant, just the production of the compounds that enhance the flavor and taste of rosemary. This means that home gardeners and trade growers will be able to produce rosemary plants with a consistent appearance but with the potential for extra flavor. The research was published in Life.

Fungi Gardening Miscellany

A Look Ahead at 2023

Phalaenopsis flower from Wikipedia, photo by Nicolas Perrault II.

Every year, there is a new crop of highlighted plants that earn the honour of “plant of the year”. For 2023, the National Garden Bureau has identified a handful of goodies:

  • Year of the Orchid – Characterized by their bilateral symmetric flowers and upward-facing blooms, orchids are a beautiful and mysterious species.
  • Year of the Amaryllis – The Amaryllis you decorate your home with during the winter holidays is a Hippeastrum. (True Amaryllis is a bulb native to South Africa with only one species, Amaryllis belladona, also known as “Naked Ladies” because of their pink flowers on stems without leaves.) Amaryllis (Hippeastrum) offered in the late fall through winter are used as forced bulbs to decorate and beautify the inside of homes during the winter. These easy-to-grow bulbs are being propagated in many parts of the world today.
  • Year of the Broccoli – my dear husband favourite veggie is also veggie of the year for 2023. Broccoli hails from the Mediterranean region and has been enjoyed there since Roman times. Other European regions eventually caught on and broccoli was popularized in France as “Italian Asparagus” in about 1650. The English adopted it about 70 years later. Pop quiz: what’s the difference between broccoli and boogers? Answer: kids will eat boogers.
  • Other plants of the year 2023 include: Rudbeckia, Spirea and Celosia.

Because I am an incurable nerd and an economist by training, I also took a look at the economic forecasts for the coming year and extrapolated my own implications for gardening. There’s a reason they call economics “the dismal science”!

Let’s start with Citibank’s Unstoppable Trends:

  • The US-China technology and trade wars will intensify, which means more supply chain disruptions. Security of supply will become more important than efficiency. I think this may mean more companies will chose to bring their production home from overseas and we are likely to see imported foods becoming more expensive or unavailable.
  • The transition to clean energy will accelerate, but natural gas is likely to remain a key fuel for some time to come. We’ve already seen how rising fuel prices drive inflation in food prices. I think we can expect this trend to continue through 2023.
  • The rush to digitization, automation, and robotics will be ongoing. This has some fascinating implications for agriculture with more emphasis on precision and robotic agriculture. See for example, this article from the EU: Futuristic fields: Europe’s farm industry on cusp of robot revolution. Home gardeners are also keen to join the robot revolution with devices that include automatic watering systems and robotic lawnmowers.
Robotic lawn mowers. Photo: Debbie Wolfe from “The Best Robot Lawn Mowers Tested in 2023” on Bob Villa’s website.
  • Aging populations and a growing global middle class will see rising investments in health care. Citibank favours “biologics”, which could mean exciting opportunities for plant scientists to tease out the medicinal properties of novel plants. The Economist also sees medicine as a smart investment for 2023, and they specifically highlight psychadelics, including psilocybin. Yes, this chemical derives from fungi, not plants. However, I can already buy mushroom growing kits from my local farmer’s market. How long will it be before I can grow my own magic mushroom?
  • Real estate investments are likely to be challenged by higher interest rates and a potential recession. Citibank favours investments in multi-family homes, e-commerce space and select office space. One lingering impact of COVID is that downtown office spaces may remain under-used. We could see office towers start to be converted into urban vertical farms.
From USDA’s article “Vertical Farming for the Future”. Indoor and vertical farming may be part of the solution to rising demands for food and limited natural resources. Photo credit: Oasis Biotech
  • The Economist notes that India’s population boom is likely to change the global economy with the sub-continent’s population set to overtake that of China in April 2023. Unlike China, which has an aging population, the majority of Indians are of working age. Many economists see this as a sign that India’s economy is likely to boom in the next few years. However, many Indians still depend on traditional agriculture, which has prioritized the protection of indigenous and heritage species of food plants. Will these heritage varieties fall victim to India’s population and probable economic booms?
  • Other trends noted by The Economist are: the war in Ukraine; high food and fuel prices; the fight against inflation; the transition to renewable energy; and China’s uncertain post-pandemic path. All these tell me that growing more of my own food will be an excellent investment for 2023.
  • RBC sees an end to rate-hiking by central banks and Canada edging closer to recession in 2023. Rising interest rates have caused housing markets to soften but unemployment remains relatively low. Rising consumer debt and ongoing inflation will probably cause people to spend less. Reuters reports that the IMF recommends the Bank of Canada to hold interest rates at or above 4% throughout 2023.
  • Economist David Rosenberg sees a serious recession as rising interest rates cause home prices fall, making it more difficult for people to service debt.
  • Royce Mendes, the managing director at Desjardins Capital Markets, also sees troubled waters ahead for the Canadian economy, and he predicts that inflation will continue to bite and unemployment will rise.

My take is that folks who bought a house before interest rates went up are likely to stay put, which I think means more homeowners may consider investing in landscaping and learning how to garden.

To all my readers, Happy New Year and happy gardening in 2023!


Giant Puffballs

Big balls of fungi are cropping up across Quebec, to foragers’ delight: Mélanie Greffard and her husband usually head out to a nearby forest or the Eastern Townships to forage for mushrooms. So the pair had quite the surprise when they stumbled upon a Calvatia gigantea — a giant puffball the size of two basketballs in their backyard near downtown Quebec City last week. It weighed in at nearly six kilograms.

“At first, it’s almost kind of scary, like, ‘What is this thing?'” Greffard said, laughing. “We were really impressed with how big it was.” Giant puffballs are large mushrooms, edible when fresh, that grow on grassy areas, often on lawns or fields. They typically appear in August and September, but puffballs the size of Greffard’s are a rare find. Greffard, who grew up in the countryside, credits her mother with getting her interested in mushroom-picking as a child.

She said this discovery was pure luck. “We’re right in the heart of Quebec City … and nature is all around us. It’s just right there, in our backyard,” she said. “It’s just really cool to see that.” Greffard found a puffball at the same spot last year, but it was in its “puffing stage,” which is when the fungus begins to change colour inside and starts producing spores and is no longer edible. So she was happy when she saw that this one was firm inside and “very nice and white,” a sign it’s still good to eat.