Humans are waking up to the realisation that the earth and it's eco-systems can only be pushed so far. With the growing concern for the environment, any sustainable material or textile has seen significant growth in the past two decades. Bamboo and bamboo fabric are considered to be fast growing sectors of this green movement. The bamboo industry in 2018 was valued at USD 68.8 billion and is predicted to grow to USD 98.3 billion by 2025. With money pouring into the industry, the question must be asked. Is bamboo sustainable? Or is it just another fad driven by greed to milk consumers conscience?
What is bamboo?
Bamboo or bamboos are a diverse group of evergreen perennial flower plants, classifying it as a grass not a wood. Due to its fast growing nature and "woodlike" strength, its easy to see why people often confuse the two.
Most bamboo species are native to tropical and warm temperate climates. South-East Asian countries like China have perfect growing conditions and naturally this is where we see the majority of the bamboo supplied from. Australia also is home to bamboo farmers, however, while we commercially grow bamboo, we have little to no bamboo production facilities for the crop. More on this later.
Image: Green coloured regions show where bamboo is grown worldwide
There are 10 different types of bamboo and over 1200 species. All with different strength's and weaknesses as a sustainable material.
Common Bamboo Plant Species
Phyllostachys edulis or commonly known as Moso bamboo can grow up to 3metres in 3 weeks putting this species at a daily growth of 14cm per day. Moso Bamboo is commonly used in the Bamboo Clothing industry for making bamboo fabric from bamboo rayon.
Phyllostachys Vivax F Aureocauslis or shortened to Golden Chinese Timber Bamboo is regarded as the best looking for the Bamboo species. As a result it is often used by the bamboo industry for flooring and other structural parts to homes.
If you would like to explore all the diverse ranges of bamboo plants and species, you can visit Wikepedia's page.
What industries are using bamboo?
Bamboo is a common food source in many Asian countries from Japan to Malaysia. The shoots are low in calories and are a great source of fibre and potassium. They have a corn-like taste and typically are boiled before eating. Pandas aren't the only ones who enjoy a tasty bamboo shoot!
Image: Tempura vegetables served with bamboo shoots.
Visit any South-East Asian country and you will see bamboo scaffolding covering the outside of buildings. Don't judge a book by its cover though, the scaffolding is deceptively strong.
The tensile strength of bamboo is just over 20% higher than that of Steel. With steel recording a strength of 23,000 PSI and bamboo coming in at 28,000 PSI.
In addition to scaffolding, It is also used in different parts of the world for housing and flooring. Bamboo is often touted as being an inexpensive alternative to hardwood flooring with similar characteristics.
Image: Bamboo scaffolding encasing a building under construction.
Until I started learning about bamboo and its uses, the thought that a woodlike grass could be turned into a super soft material was foreign to me. However, bamboo fabric is not a new concept. The earliest indication of bamboo fabric was from US patents created in 1864 held by Philip Lichtenstadt. Since then it took nearly a century for it to become more popular. Its rise to fame coming largely from it being a sustainable crop and the fabric wicks moisture making it ideal for clothing in humid climates. On top of this, its super soft!
Made from bamboo products across nearly every part of the household have exploded in the last 10 years. From toothbrushes, to reusable cutlery and even bamboo straws. Bamboo makes a great plastic alternative and an ideal eco-friendly material for homewares.
Image: Various bamboo homeware products.
Where does the sustainability of bamboo come from?
Bamboo's sustainability claims come primarily from its growing and farming friendly properties. Its environmental impact as a crop, relative to other commonly grown crops is where it shines as an eco-friendly alternative.
The speed at which bamboo grows
Bamboo is one of the fastest growing plants on the planet which is where its sustainability claims come from. One species holds a Guinness World Record for the fastest growing plant at 91 cm per day which is absolutely crazy when you think about it. While not all species grow at the same rate, bamboo is known across the board for its crazy growth rate.
Image: Kyoto Bamboo Forest.
The speed at which bamboo grows means that its output per square metre per year is far higher than a crop that can only be harvested once or twice a year. As a result, less farmland is required to meet consumer demand for bamboo fabric.
The destruction of habitats to install monoculture eco-systems (farmlands dedicated to one crop) can have a severe environmental impact over time. While this kind of agriculture practise has sustained human development, we are now finally pricing in the long term side effects.
Bamboo has far less of a negative effect compared to cotton. But is not without its faults. Certain species can be considered invasive due to the speed at which they grow and its ability for its roots to spread underground and rapidly expand over an area. While this is an issue if left unchecked, bamboo farmers install underground railings to prevent the roots from expanding and thus mitigating the downside.
Depending on the industry and crop you are comparing it to, bamboo has varying degrees of superiority when it comes to water efficiency. Lets take cotton as an example. Bamboo uses 1/3 of the water compared to cotton and requires very little to no irrigation. As populations swell, we need to be increasingly protective of the precious water we do have. A crop that requires less water per output makes it more eco-friendly and sustainable through purely requiring less resources to produce and process.
Soil Erosion & Health
When harvested, bamboo is cut about one to two nodes from the ground. This means the soil does not need to be dug up and the existing root structures can remain in place. When harvesting, farmers often let the leaves decompose around the trees as a fertiliser to give back to the soil.
Image: Bamboo stumps post harvest. Cut two nodes above the base.
Compared to organic cotton or hemp, where when harvested the whole plant and root system is torn from the ground. Continual use of the land for crops like this leads to soil erosion and degradation of natural minerals.
Overall as a crop, bamboo is an eco-friendly alternative to some of the current mainstream crops used for fabrics and should silence any critics questioning just "how sustainable is bamboo?"
Is bamboo fabric sustainable?
This is contentious. Many brands claim to have sustainable bamboo clothing. However the determining factor is really dependent on the manufacturing process used. There are several ways to manufacture bamboo fabrics, all with varying degrees of pros & cons relating to being eco-friendly and sustainability. In some instances bamboo clothing can be just as harmful to the environment as its other fabric counterparts. Lets dive into the ways bamboo is turned from plant into bamboo fibers and then into clothing.
What is the difference between bamboo linen, lyocell & rayon?
There are three ways of turning bamboo into a fibre which then can be used in the production process of creating clothes.
Rayon production process
Bamboo rayon is made through the viscose process. The cellulose material, in this instance bamboo wood chips, are dissolved in a chemical solution containg Sodium Hydroxide, Sulfuric Acid & Carbon Disulfide. This produces a viscous bamboo wood pulp substance. The pulp is then spun into bamboo fibres which then be configured into fabric and used to make clothing such as bamboo socks. This is where bamboo falls down as a sustainable material. The carbon disulfide used in the rayon process can be quite harmful to not only the environment but also to toxic to the workers involved. How manufacturers handle this waste can determine just how "sustainable" and environmentally friendly the product is. Several governments now force companies to state whether the the bamboo product is rayon as the consumer deserves to know.
Lyocell fibre or commonly known as Tencel fibre is a semi-synthetic fibre known for its softness and breathability. The processing takes place over 9 steps:
- Hardwood such as bamboo or oak are broken down into chips and loaded into a vat to soften
- Pulp is then washed and in some instances sanitised
- The wood pulp is then dissolved in heated vats of amine oxide to dissolve the cellulose
- Once the cellulose had dissolved into a liquid form, it is then filtered and pumped through spinnerets
- The solution is put through a spinning process turning the liquid cellulose into cellulose fibers
- These fibers are then washed and returned to a vat of amine oxide to set
- Once set, the bamboo lyocell fibres are dried and lubricant is applied
- From here the fibres are carded which helps to separate and order them into a useable consistency
- Finally the lyocell bamboo fibres are cut to suit whatever bamboo clothing they will be used.
Lyocell is considered a more environmentally friendly process than the rayon process purely because the chemicals are less harsh and not as toxic. That being said, its important that the manufacturer uses a closed loop system. This ensures chemicals are correctly handled and disposed of. The manufacturing process for our bamboo sheets utilises the Lyocell method. When deciding on a manufacturer, we actively avoided Rayon based on its harsh chemical treatment.
Mechanical process (bamboo linen process)
This process is the same eco-friendly one used to produce linen from flax or hemp. The wood parts of the bamboo plant are crushed mechanically. Natural enzymes are then used to break the bamboo down into a mushy mass whereby the cellulose fibers can be spun into a yarn in a similar process listed above. The end result is bamboo cloth ready to be used as a textile. Bamboo linen is commonly used in bamboo bedding products.
Mechanical process results in minimal pre-treatment, which is a massive sustainability advantage compared to lyocell and rayon. The process is very labour intensive and is why you don't see as much bamboo linen on the market compared to rayon and the growing lyocell market. This process produces truly sustainable bamboo clothing but at a much higher cost.
So, is bamboo eco-friendly?
Eco-friendly is measured on an item's relative impact on the planet compared to other items in their category. As a crop, bamboo has many advantages over others and it definitely deserves its claim as being highly sustainable so long as its farmed responsibly. As a fabric, bamboo lyocell is definitely preferred but a closed loop factory that is conscious about its rayon production process is miles better than the cotton alternatives.
If you haven't made the switch, try our bamboo socks or bamboo toothbrushes. Its an easy sidestep away from plastic and great starting point for your foray into bamboo land. Just ask any panda, bamboo is the shoot.