08 Nov

Material Guide: How Sustainable is Hemp?

I’ve got sad news for all you rebels hoping to roll a joint out of a t-shirt! Hemp is actually the “sober cousin” of marijuana. Industrial hemp contains only a tiny amount of the psychoactive component of cannabis. So the only high you’ll get from hemp fabric is the moral high-ground you’ll stand on knowing you’re wearing a sustainable fabric!

In fact, industrial hemp is the fashion equivalent of the boring sibling who wants to stay home every weekend and knit socks for fun. So basically, hemp is my ideal friend! But despite its boring properties, hemp’s association with bad boy cannabis has copped it a bad rep for a long time now.

It also doesn’t help that in the last few years, hemp clothing has been associated with baggy grunge-style clothing in khaki hues. Not that there’s anything wrong with unwashed hippy clothing if you happen to be an unwashed hippy, but the trend certainly hasn’t done much to improve hemp’s image among the general populace.

But can hemp redeem its image? Many think that it can. And the environmental benefits of hemp cultivation, combined with its durable characteristics as a fabric, have many hoping that it can feature in clothing that both feels and looks great, by even the highest of standards (pun intended).

So what is hemp?

Hemp actually has a very long history of being used as a fibre, in fact, it has been cultivated for thousands of years and on almost every continent. It has been used in clothing, ropes and sails – in fact, rumour has it that the word “canvas” is derived from “cannabis”.

Hemp is a type of “bast fibre” which means it’s one of a number of natural fibres derived from the stems of plants such as flax, jute and stinging nettle. The fabric has various natural advantages such as keeping you warm in winter, cool in summer and even protecting you from UV rays.

The fibre produced from pure hemp is similar to linen in texture. It can also be blended with other natural fibres to create fabrics with the durability of hemp and the softness of cotton or bamboo.

But why all the fuss about the little green leaf? Is it really any different to other natural fibres?

What makes hemp a sustainable option?

It’s no coincidence that hemp bears the nickname weed. A densely growing plant, hemp literally chokes out any competing plants. This means harsh chemical herbicides aren’t necessary. Hemp also naturally reduces pests, so no pesticides are needed. Amazingly it also returns 60-70% of the nutrients it takes from the soil.

Not only is hemp gentle on the earth, it also requires very little water, especially when compared to cotton, which, according to Slate uses “about 50 percent more water per season than hemp.” But that’s not all. According to the same article, “When you add processing into the equation, cotton uses more than four times as much water as hemp.”

Hemp also requires a relatively small amount of land to cultivate. According to the Guide to Sustainable Textiles, this means it can produce up to double the fibre yield per hectare than cotton. So from an environmental perspective, the benefits of hemp are pretty clear. But how does it compare once we start processing the raw product into a fabric?

How is hemp turned into a fabric?

Hemp fabric is made from the long strands of fibre that make up the stalk of the plant. These fibres are separated from the bark through a process called “retting.”  These fibres are then spun together to produce a continuous thread that can be woven into a fabric.

The various stages of this process can be done organically through a mechanical process that requires no chemicals. However, many companies now produce hemp fabric chemically, in a process that is much more intensive on the environment, but faster and cheaper to create.

The impact of the fabric doesn’t just stop once it has been woven, either. Once the fabric has been created, it may be dyed, which again can result in various environmental outcomes, depending on the technique used.

So the production phase is a bit less clear-cut. Although hemp is a sustainable crop to grow, we still need to be sure that the process being used to turn the plant into a fabric is low-impact. Producers have a responsibility to ensure their manufacturing process considers the environment, their workers and the consumers, along with profitability.

So, what’s the verdict?

The good news is that hemp constitutes a highly sustainable, low-impact crop that can be converted into fabric sustainably. It’s important to make sure, however, that companies are not just “greenwashing” their hemp. Wondering where to start looking? Check out the Good On You app to see how brands using hemp rate on issues that are important to you!
Do you know any great brands using hemp in their clothing? Let us know in the comments!

Editor's note: Feature image via Unsplash.

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