Is Hemp Sustainable? Hemp Fabric & Material Rundown

A sustainable hemp leaf wearing pants made of hemp, running about.

How sustainable is hemp, and is this useful crop the future of ethical fashion?

As cannabis legalization wafts mouth-wateringly across the globe, most people are asking different questions.

But it appears that we can now start talking about hemp without causing so many pearls to be unreasonably clutched.

Hemp has over 25,000 uses, and might be the next big thing when it comes to sustainable fabrics and building materials.

So where does it come from?

What is hemp?

Hemp stems from a strain of the Cannabis sativa plant. The words hemp and cannabis both originate from the same proto-Germanic root word, hanapiz, but it’s not the roots (or the flower buds) that are important to making hemp.

A farmer checking on a  hemp plant growing on their indoor farm.

For thousands of years, humans have used hemp in a variety of interesting ways; as a textile, a building material, paper, a source of oil, feedstock, biofuel, and even modern medicinal treatments.

When it comes to sustainable fabrics in particular, hemp is one of the most promising options we have for reducing the amount of resources and energy used, and waste produced in the fashion industry.

Hemp is cheap, versatile, easy to grow and process and provides us with countless finished products.

So, why aren’t we using more of it? The answer lies mainly in its troubled history.

A brief history of hemp

Humans and hemp share a long and storied history together; some of the earliest evidence of the use of hemp for food and clothes dates back to around 10,000 years ago.

Vikings used hemp for clothing in the middle ages along with flax and nettle fibers; and many artists, including Van Gogh used hemp paints and hemp as a canvas (another word originating from cannabis) to paint on.

Hemp shoes on display at the Xinjiang National Museum, China.

Even the British Empire was at one time reliant on hemp sails and ropes for its Navy, and in their colonies of the 17th century North American continent.

But by the time plastics and cotton were commonplace, the hemp industry became the target of propaganda campaigns which we still feel the effects of to this day.

Hemp production was and is still caught up in hysterical, malicious, and confusing legislation surrounding the prohibition of the therapeutic or recreational use of marijuana; something which is slowly changing worldwide.

Hemp clothing for sale at an organic clothing store.
Image by Dave O via Flickr

Competition with the cotton and polyester industries no doubt contributed to its decline, and by 1970 in the US the Controlled Substances Act made the growing of cannabis and hemp illegal.

Things are starting to change, however, with loosening regulations and renewed interest in the estimated 25,000 possible products that can be made from this sustainable material, giving way to new farming and growing techniques.

How is hemp fabric made?

Fabrics like hemp cotton and hemp linen blends are common and comfortable, and both new and traditional methods are used to weave them.

Intricately stitched and designed hemp linen fabric.
Image by titanium22 via Flickr

The traditional process of making hemp fibers for fabric involves a few steps, which we’ll go over briefly (or you can check out the video below):

Cultivating the plant. Since the desired fibers come from the stem of the plant, seeds are sown in high density to produce tall, spindly plants that are relatively close together.

Harvesting the crop. After flowering and before the seeds have time to set, the fibers are fine and strong enough to be processed, and the stems are at peak length, so the plants are harvested.

Retting and soaking the fibers. This is a sort of fermentation, where the microbial action of bacteria and fungi in the plant break down the carbohydrates that hold the hemp fibers together. It’s done via soaking in water or simply by leaving the plants on the ground for a few weeks.

Breaking down the stems. The stems are then ready to be pounded to release the fibers. To do this, they’re broken up and beaten in a process called scutching, to separate them from the core of the stem.

Hackling, roving, and shaping. Hackling is the term for combing the fibers into a continuous “sliver” thread, which is necessary for comfortable pieces of clothing. The sliver is then twisted and stretched into a uniform thread, which is wound on bobbins for spinning.

Spinning the yarn. Traditionally, spinning hemp results in a coarse, rough yarn, but more modern approaches have been designed to soften this, and well-made, blended hemp can produce a fabric that’s indistinguishable from cotton.

Here’s a video showing a bit of this process:

Another documentary I really enjoyed about hemp processing is this spanish documentary below with english subtitles, it covers a handful of ways of working with hemp. It’s also just a super relaxing, chill documentary:

Is hemp sustainable and ethical?

In terms of quality, there’s no concern about modern hemp competing with cotton or many other textiles; as modern manufacturing techniques make it more than possible to create high-quality hemp garments – a far cry from the scruffy, abrasive stuff of the past.

Hemp cloth actually outperforms most fabrics in terms of durability, aside from silk and wool, making it a perfect option for long-lasting clothing; a key factor when talking about sustainability.

Yarn made from a blend of hemp and wool.
Image by inger maaike via Flickr

Regenerating worn-out hemp fabric can actually make it more durable by improving its resistance to abrasion and pilling, a unique ability that other fabrics like cotton or polyester lack.

But the benefits of making our clothes from hemp don’t stop there.

As a crop, hemp is also fantastic at carbon sequestering, possibly more than any forest or commercial crop currently in use. Compared with cotton monoculture farming, its major competitor, hemp provides three times the yield in the same space, and substantially less water – resulting in a nearly 80% reduction in agricultural costs overall.

Lots of hemp plants growing on a farm in Maryland, USA in 2020.

Industrial hemp generally doesn’t require many harmful pesticides to grow, although there are pests associated with the crop; some of this may be due to the lack of any hemp-specific herbicides on the market, but it’s often recommended to just keep up with mechanical weeding on large scale hemp farms.

Even when compared with flax, another good candidate for sustainable textiles, hemp requires a lot less fertilizer to grow. And growing it can even help with soil health and weed suppression, as it’s often grown with a diverse number of cover crops.

A hand scooping out some cover crop seeds to be sown alongside hemp.

Hempcrete can even be used to construct buildings and infrastructure, and is also able to store carbon once made, compared to something like Portland cement-based concrete which actually releases more carbon over time once poured.

All of this sounds great, but it’s really the fabric-making process that needs to be scrutinized when talking about hemp sustainability, as replacing a problem crop like cotton in the future would be incredible for the environment.

The retting process, which is when the stems are soaked to separate the fibers from the less useful starchy matter, is the main area of pollution and environmental issues.

Traditionally, water retting involves soaking the hemp stems in a ditch, and this inevitably leads to water pollution from all of the released plant acids. It also uses a substantial amount of water, and is now prohibited in most European countries.

In place of water retting, most Western hemp producers now use dew-retting – where the stems are left out in damp areas on the ground; a common practice in places like Normandy, France.

This takes longer but uses fewer resources, and there are other ways to make the process more efficient.

A farmer holding up an organic hemp plant seedling.

Steam explosion processing has the potential to be used to separate hemp fibers quickly and to produce flame resistant fibers, which particularly profitable when used at scale due to the usefulness of fire-retardant clothing.

Working to perfect the most efficient cocktail of microorganisms responsible for the traditional retting process could also help, and would provide a low-tech alternative to steam retting which could allow developing countries to remain competitive in the market.

But it’s not just the retting that needs attention, as in order for hemp to compete in quality there are likely going to be some chemical treatments involved, if the current standards of cotton fabric in the fashion industry is anything to go by.

These can include things like caustic or acid rinses to improve softness and heavy metal dyes for color, and will bring with them the environmental challenges associated with any textile industry.

Tannery pools filled with chemicals in Morocco.

This creates opportunities for the unethical labor practices all too common in unregulated regions, where textile laborers may be forced to work with dangerous chemicals without appropriate protective gear. Though, as a whole, the process is a lot less intricate and labor-intensive than cotton, leaving less room for human rights abuses.

Another concerning part of the hemp industry is the greenwashing of its usefulness as a fabric or to the sustainable agriculture movement in general.

Hemp, as a low-impact eco friendly crop, lends itself to genuine sustainability claims – but it’s easy to overlook the potential for environmental damage caused further down the chain.

Interesting experiments in the industry have been taking place as well; the cotton gin, a technology that originally helped cotton outcompete hemp, shows promising adaptability to the processing of hemp.

And while concerns over switching from one industry to another exist, the issues faced by hemp farmers right now relate more to the booming, oversupplied legalized cannabis markets than the issues with hemp production itself.

So, what needs to be done to popularize sustainable hemp fabrics and textiles?

What does the future of hemp look like?

There are both consumer and regulatory drivers that need to be addressed before hemp clothing can be profitable.

Compared to plants like cotton or bamboo, hemp isn’t a very popular or profitable crop to farm, and the low supply creates an expensive end product. And with most fast fashion brands chasing cheaper prices, it’s hard to imagine how that could change.

The real issue is that hemp production is a matter of legislation – not a lack of interest.

Currently, the US Department of Agriculture and the FDA restrict the sale of hemp material to states with pilot programs and the transport of plants to states currently enrolled in these research programs.

These restrictions stifle the potential of hemp as an alternative to the far greater cotton industry, and this is one of the key angles from which advocates for sustainability need to approach the situation.

On the other side of the Atlantic, the EU is somewhat ahead of the curve and already incorporates hemp into discussions and roadmaps for a more sustainable textile industry.

Adding to this is the fact that hemp can be grown in the temperate climates of Northern Europe, and this is without the use of genetically modified hemp seeds as well. So, this amazing plant may be making a comeback very soon and bringing huge economic gains (PDF) to those at the forefront of its resurgence.

Final thoughts

Hemp appears to be a wonder crop that’s been unfairly restricted by textile competitors and regulations until recently.

It’s one of the most versatile plants there is, and its cultivation brings environmental improvements over both its commercial competitors and many other plants in terms of carbon sequestering and soil quality.

What’s your favorite brand using hemp fabrics?

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