How truffles are grown: the secrets behind truffle foraging and farming

Truffles are one of the most luxurious foods in the world. Chefs call them “the black diamond of the kitchen.” A few truffle shavings can turn a plain pasta dish into something amazing thanks to their rich, earthy aroma and flavour. But truffles are more than just a luxury food. They are rare, hard to grow, and have a fascinating story. They are also a big part of European history and culture.

But what are truffles, exactly? Where do they come from? And why are they so expensive? Let’s dig in to find out.

What are truffles? 

Truffles are like treasures from the forest - rare and full of mystery. They are a kind of fungus, just like mushrooms, but unlike mushrooms, they grow underground. They belong to a family of fungi called Tuber.¹ Truffles form under the roots of certain trees, hidden beneath the soil. Their main job is to spread spores — tiny, seed-like particles that help make new truffles grow.¹

They can’t be grown easily like carrots, potatoes, or tomatoes. So you won’t find them in many places. They don’t stay fresh long either, so when someone gets their hands on them, it’s a big deal. If you’re lucky enough to get truffles, consider them a treat and enjoy them while they're fresh. Eating them is like having a tiny but important celebration on your plate. Let’s explore what people from different times and places have thought about truffles. 

Cultural importance of truffles 

People have been eating truffles for thousands of years. In ancient times, people in places like  Egypt, Greece, and Rome enjoyed them.² Nobody knows exactly how the first truffles were discovered, though it’s thought that people noticed pigs digging them up, and they got curious and tried them for themselves.

During the Middle Ages, their popularity dropped drastically, and truffles suddenly fell out of favour. They were associated with witches, and many people were too scared to eat them.³ It wasn’t until the Renaissance that truffles regained their popularity. King Louis XIV of France brought them back into fashion when he served them at feasts and even tried to grow them in his royal gardens.   

Today, truffles are still seen as culturally important, especially in places like Italy and France, where truffle hunting is a special and cherished tradition. Truffle foraging and festivals keep the tradition alive and preserve the knowledge of the best truffle-producing areas.

Types of truffles and how to use them

There are over 200 species of truffles in the world.⁵  Here are just a few of the most popular varieties.

White Truffles (Tuber magnatum)

These are the most expensive truffles. They have a very strong aroma. They are almost always shaved fresh and raw over hot dishes like pasta, eggs, or risotto at the very end of cooking. Their flavour is delicate and would be lost if cooked. You only need a tiny bit because their flavour is so powerful.⁶

Black Truffles (Tuber melanosporum)

The famous black truffle is also known as the Périgord truffle. These have an intense, earthy, and complex flavour.¹  They are often used as a topping or garnish, sliced or grated over dishes, or lightly mixed into sauces and oils. Black truffles can be used raw or cooked. Their flavour goes well with red meats, cheeses, and pasta.^{6 7}

Summer Truffles (Tuber aestivum) 

These have a milder, more subtle aroma and taste. They are more common and less expensive, making them a good way to try truffles for the first time. They can be used fresh, shaved over salads, or infused into oils.⁶

Burgundy Truffles (Tuber uncinatum)

These are harvested in late autumn and have a delicate aroma and flavour. They have less flavour than the Périgord truffles, but they are cheaper. It’s best to use them in cooked dishes, but they can be used raw.⁶

Buying truffles and truffle products

Truffles might be rare, but there are still ways to enjoy them at home. 

If fresh truffles are too expensive or hard to find, you can try truffle-infused products like truffle oils, salts, or butters. Just be sure to check the label to make sure they are made with real truffles, not artificial flavours. A little bit of these products can add a lovely truffle flavour to your meals.⁶

How truffles grow

Growing a truffle takes teamwork between trees, soil, and fungi. Truffles don’t just sprout up anywhere. They have a special bond with certain trees, forming a partnership known as mycorrhiza.¹ In this special relationship, the truffle fungus helps the host tree by bringing in minerals and water from the soil, while the tree shares its sugars with the truffle. 

Truffles are picky about their tree companions. They prefer hanging out with broad-leafed trees like oaks, hazelnuts, and beeches.¹ Truffles also have soil and climate preferences. They thrive in soil that’s slightly alkaline, with a pH level between 7 and 8. They like well-drained soil with proper moisture levels, so they don’t have pools of water around their roots. They also prefer climates with warm summers and cool winters, just the right balance to keep them growing. 

Even with cultivation and perfect conditions, truffles are in no rush. After the tiny truffle spores connect with the tree roots, it can take anywhere from 5 to 10 years, and sometimes up to 15 years for the truffle to fully mature underground!^{1 9}  It’s like waiting for a delicious surprise to ripen. 

How truffles are found

One of the truffle’s most remarkable features is its powerful aroma. But, as truffles grow underground, they’re very tricky to find, even for those with a great nose. But when they are ripe, they release a very strong and unique smell. This powerful aroma attracts wild animals, who dig them up and eat them. When the animals then spread the truffle spores through their waste, it helps new truffles grow elsewhere.¹

For centuries, pigs were used to hunt for truffles because they are naturally drawn to this smell, especially female pigs.¹¹ The scent is similar to a natural chemical found in male pigs, which attracts females. But pigs love the taste of truffles too. And it’s very hard to stop them from eating truffles once they find them. Because of this, trained dogs have become the more popular choice for truffle hunters today.¹² Dogs have an amazing sense of smell, much better than humans, and can be trained to find truffles deep underground without eating them or damaging the delicate roots of the trees. Many dog breeds can be trained for this job, including Spaniels, Labradors, and even Chihuahuas for smaller areas.¹²

Why are truffles rare and expensive? 

Truffles are so rare and costly for a few key reasons:

Limited places to grow

 Truffles need very specific environments to grow. They are mostly found in certain parts of Italy, France, and Spain. But they have been successfully cultivated in other countries like Australia, Canada and the United States, where conditions are right. This small range of places where they grow naturally or can be cultivated makes them scarce. ^{9 11}

Delicate environment

The precise conditions truffles need are easily upset by things like climate change, deforestation, and over-harvesting or improper harvesting by humans. Changes in rainfall patterns can also affect truffle growth. This makes it harder to find wild truffles.⁹

Hand-picked harvest

Because they grow underground, truffles can't be harvested by machines. Hunters and their trained dogs must search and dig each one up carefully by hand. This takes a lot of time and effort, adding to the cost.⁶

Short season

Truffles only grow and ripen during specific times of the year, which further limits how many are available.⁹

Lose aroma quickly

Once a truffle is dug up, its unique scent begins to fade away quickly. This means they must be transported very fast to customers to keep their strong flavour.⁶

Truffle farming 

For most of us, growing truffles is not something we can easily do. But truffle cultivation is possible. And thanks to clever techniques developed in France in the 1970s, truffle farming is on the rise.¹¹ Around 95% of truffles in France come from farms, not the wild.¹⁴  In 2020, French scientists achieved a major milestone by successfully growing the valuable white truffle (Tuber magnatum), which had been nearly impossible to farm before.¹⁵ This breakthrough opens up exciting possibilities for truffle lovers worldwide.

Farming truffles involves mixing truffle spores with tree roots and planting them in special orchards under carefully planted trees with plenty of good soil. With the right conditions, it’s possible to create truffle havens. Not only can this satisfy our truffle cravings, but it also boosts local economies, supports biodiversity, and keeps our soils healthy. ¹

But it’s still not easy to farm truffles. It takes many years to set up a successful truffle orchard. And even then, there’s no guarantee of a good harvest, especially with challenges like climate change. 

Sustainability of truffles 

Wild and farmed truffles are feeling the heat

Climate change and disappearing forests are making their natural habitats less suitable.¹⁶  This could reduce truffle yields and increase prices. A 2019 study predicts truffle production in France, Spain, and Italy will decline even more.¹⁷ with rising temperatures causing truffle-growing areas to become drier. Farmers are adapting by using advanced irrigation systems, but it's not always easy or cheap.¹⁴

The future of truffles may be different

Cooler climates in places like the UK, Scotland, and Ireland might become the new hotspots for truffle farming. These regions could offer the right conditions for truffles to thrive, ensuring a steady supply for the future.¹⁴

In the end, truffles are still a bit of a mystery. They're tricky to grow and depend on a climate that's changing fast. But with science, innovation, and a bit of patience, scientists and foragers are working hard to keep these delicious fungi on our plates for years to come.

A luxury to appreciate

Truffles are a very special kind of food. They grow underground and need just the right mix of fungus, trees, soil, weather, people (and animals) working together. When you learn how truffles grow, how people find them, you begin to understand why they are such a luxurious food. As climate change makes them even trickier to find, their value is on the rise. So, if you’re lucky enough to enjoy a dish sprinkled with truffle, consider it a delightful indulgence and something very special!