Mushrooms are used in cuisines all over the world. They are also used in skincare treatments, for medicinal and recreational purposes, and even for textiles. One mushroom in particular, the Amadou, has a felt-like texture that was traditionally used in parts of Europe for making hats, a craft largely forgotten but still practiced in at least one community in Transylvania. And today, the mushroom is trending as a new, more ethical form of animal-free leather.  

Since at least the 1950s, scientists, entrepreneurs and artisans have experimented with using different elements of mushrooms to recreate the texture and durability of certain man-made materials, such as paper. More recently, companies have devoted research and development dollars to mycelium, the stringy and durable root structure of certain fungi. The appeal? Mycelium grows quickly using relatively little space, energy, chemicals or water, and it’s naturally biodegradable. It has been used successfully at scale for molded packaging to replace styrofoam, as building insulation, to create lampshades, and as a plant-based meat. 

The next frontier for scale is to use mycelium as the basis for an alternative to animal and synthetic leathers. 

From Fungi to Leather

In the fungi kingdom, mushrooms are the above-ground fruit of a delicate-looking but robust underground network of interconnected microfibers called mycelium. This network can be recreated with relatively little time, space and energy in grow labs. 

Indoors, mycelium is nurtured by controlling airflow, CO2, temperature and humidity. The cells feed on organic matter, which in lab conditions is often sawdust but can be almost any agricultural byproduct or waste. The mycelium fibers develop and replicate, interweaving with each other and then, at the stage when they would normally start to produce mushrooms, they are instead redirected to grow into almost any desired shape and size. For mushroom “leather,” this means growing the mycelium into thin, flat mats. 

The entire growing season is completed within as little as two weeks at which point the product is biodegradable and compostable. The process itself is completely circular.

The resulting mats of mushroom leather can now be finished — e.g. tanned, dyed, embossed, pressed — much like animal and synthetic leathers. As with other leathers, its scent will ultimately be most impacted by whatever is added to it in the finishing stage, and those additions may compromise the mushroom leather’s ability to biodegrade or compost. 

Is Mushroom Leather Better For the Environment?

The development of plant-based leathers has the potential to solve the ethical and environmental problems animal and plastic-based synthetic leathers face. Here are some of the many benefits.

Growing mycelium is low-impact on the planet because it:

• Grows in weeks as opposed to months and years for animals
• Requires relatively little space or energy and most of the waste is compostable 
• Eats agricultural byproducts, even mushroom leather itself
• Requires no plastic or toxic chemicals for its production
• Is naturally absorbent, antibacterial and antimicrobial
• Is compostable 

Compared to animal leather: 

• No animals are involved 
• It requires less chemical treatment than tanning and dying animal hides, practices which lead to water pollution and can be hazardous for workers

And compared to other synthetic leathers:

• It’s biodegradable
• Does not require plastics, like polymer or PVC, which are toxic and polluting.

However, mushroom leather can become more environmentally impactful as it moves through the supply chain. Its low-impact status can be compromised if other materials and chemicals are introduced into the finishing or fabrication stage. For example, Bolt Threads’s Mylo incorporates plastic and therefore is not biodegradable. 

Mushroom Leather In Action

Two of the most visible producers of mycelium-based leather are Bolt Threads (founded 2009) and MycoWorks (founded 2013), each of which is bringing a scalable offering to market in 2021. 

Stella McCartney is consistently at the forefront with experimental textiles to meet the needs of her animal-free eponymous fashion label. She works closely with Bolt Threads, using its product Mylo, for prototypes. First, in 2018, they produced a small number of mushroom leather Falaballa handbags. Then, in 2020, McCartney, along with adidas, Kering and lululemon, formed the Mylo Consortium to help subsidize research and development.

Most recently, in March 2021, McCartney debuted the first garments made from Mylo (for viewing only): a bustier and trousers. The first major release of Bolt Threads at scale however, will come from adidas in late 2021, where a natural rubber-soled Stan Smith will use Mylo for its upper.

Another prominent developer of mycelium-based leather is MycoWorks. In collaboration with luxury brand Hermès, they developed a bespoke mushroom leather called Sylvania to incorporate into the Hermès Victoria bag. In late 2021, MycoWorks will release Reishi, a line of mushroom leather available to all fashion brands.

Even some smaller companies, founded on eco-conscious principles, are having fun exploring the medium of mushrooms too. For instance, streetwear brand Eden Power Corp’s latest collection featured Amadou-mushroom hats.

The overall market for bulk leather is around $80 billion USD annually, according to the Material Innovation Initiative, and sales of finished leather goods total more than $400 billion USD. As big as the market is, there’s clearly a lot of room for alternative leathers to find their place, especially for the growing number of conscious consumers out there.

Thankfully the companies we mentioned are receiving the necessary funding to compete with traditional leather manufacturers. In 2018, Bolt raised $123 million USD, and is currently building a larger plant, while MycoWorks gathered $62 million USD in investments and opened a new facility in California last year.

The Future of Mushroom Leather

2021 could be the year when mushroom-leather products become more widely available to designers and to consumers. Boosters of plant-based leathers are justified in lauding mycelium for its versatility and its potential as a viable proxy for leather in apparel, shoes and accessories. However, mycelium is only as ethical and low-impact as the designers who use it. They make the decisions that ultimately either preserve or compromise its environmental integrity. 

For now, the most pressing questions are whether the production of mycelium and the use of mushroom leather will scale, and at what cost for wholesale and retail. But it does seem possible that in the not-too-distant future, mushroom leather will replace many of the animal and plastic leathers in our closets, homes, cars and beyond.