Hemp

Agraloop BioFibreAltagAnti-FungalAnti-MicrobialBeautyBreathableCelluloseClarusCompostableFood & BeverageHempLightweightLow-CarbonMohawk RenewalMould-ResistantMoulded FibrePackagingPapacks Fiber BottlePaperRecyclableRegenerativeStrongTextilesThe Beauty LoopUV-Resistant

WHAT WE SAY:

Restricted by overzealous governments in the UK and US, hemp was seen for much of the 20th century as only being good for dope or, at a push, rope. Thankfully, one of humanity's oldest crops is now having a long-overdue comeback.

Textiles, insulation, biofuel, paper, cosmetics, even food and drink – there seems to be no limit to what an enterprising mind can do with the Cannabis sativa plant. If we are serious about phasing out plastics, then tapping into the myriad opportunities hemp offers is a no-brainer.

Hemp thread / Source: Shutterstock

WHAT IS HEMP?

Hemp is a cultivar of the Cannabis sativa plant that has been specifically grown for use in industry, rather than for its psychotropic purposes. The word 'hemp' can refer to the plant itself, any part of the plant, or any of its derivatives.
The bast fibres, taken from the phloem or bast on the inside surrounding the stem of the plant, can be used to make textiles. The woodier, inner hurd fibres can be used in construction, animal litter and bedding. After they are harvested, the seeds are dehulled with gravity separation and vibration to be used in food, drinks, animal feed and nutraceuticals.
An annual plant, hemp can be grown according to different heights, densities and cultivation methods, depending on its intended use, with a focus on either its fibre, seeds or flower.
Hemp is a fast-growing crop, needing just 90-120 days before it can be harvested, compared to around 160 days needed for Cotton, with a comparable amount of energy required and CO2 emitted for crop cultivation and fibre production. Moreover, hemp often requires less land and water than cotton, and has the highest yield per acre of any natural fibre.
When it grows, hemp can replenish nutrients in the soil, while its root system also minimises erosion. As such, it can be used as a rotation crop and even extract pollutants like heavy metals.
The crop can capture carbon twice as effectively as forests. Industrial hemp absorbs between 8 and 15 tonnes of CO2 per hectare of cultivation, while forests typically capture two to six tonnes per hectare, depending on variables such as region and tree species.
A low-maintenance crop which can be grown in a range of climates and soil types, hemp does not require insecticides, fungicides or herbicides.
Hemp can be indefinitely recycled, and if it is left untreated or appropriately processed, it is completely biodegradable and compostable.

KEY PROPERTIES:

Anti-Fungal
Anti-Microbial
Breathable
Compostable
Lightweight
Low-Carbon
Mould-Resistant
Recyclable
Regenerative
Strong
UV-Resistant

INDUSTRY:

Beauty
Food & Beverage
Packaging
Textiles

AVAILABILITY:

Mass Market

DIVE DEEPER:

Hemp was one of the first materials to be spun into a usable fibre, with archaeologists finding 9,000-year-old woven hemp material at the Neolithic site in Çatalhöyük, Turkey. Other evidence has been found on Yangshao pottery, dating back 7,000 years.
In the US, hemp production was strictly controlled by the Drug Enforcement Agency from the 1950s. These restrictions were eased first by the Agricultural Act of 2014, with further relaxation under the Agriculture Improvement Act of 2018. The total value of hemp grown in or under the protection of the US has risen drastically since these changes, reaching USD 824 million in 2021.
The percentage of tetrahydrocannabinol (THC), the psychoactive component of cannabis, in industrial hemp is very low. By law in the US and Canada, hemp must have no more than 0.3% THC. In the EU, the percentage of THC permitted in hemp will rise from 0.2% to 0.3% in 2023. Anything above this is considered to be marijuana and is restricted. Industrial hemp usually has high levels of non-psychotropic cannabinoids.
Hemp is a hardy crop that can be grown in most climates and environments, with plantations spreading as laws are relaxed in various territories. Major producers of hemp include China, the US, Canada and France.
For fibre used in Paper, insulation and textiles, densely spaced tall plants with small stalks, less leafy material, and a harvest height of ten to 14 feet are preferred. For seeds and grains used in food and body products, a shorter harvest height of six to nine feet is ideal. For CBD-based pharmaceutical alternatives, well-spaced – usually female – bushy plants are preferred, with wide branching to promote flowers and buds, and a harvest height of four to eight feet.
To make fibres from hemp, the plant is cut, then undergoes ‘retting’ to break the bonds between the bast and hurd fibres. Chemicals can be used to speed up the retting process but should be avoided wherever possible due to the potential harm to the environment, as well as a reduction in fineness, twist and strength of spun yarn.
To separate bast and hurd fibres, the hemp stalks are further broken by machine, then scutched and hackled to scrape and clean the bast fibres, which can be used to make 100% hemp textiles or be woven with cotton, flax, Silk or other fibres.
To make textiles from hemp, its fibres are separated and cleaned before being spun into a long, continuous yarn, which is then knitted or woven into fabric. While it is absorbent, strong and UV-resistant, pure hemp textiles can also be stiff, heavy and abrasive. Consequently, hemp is sometimes softened with acid rinses and caustic soda, organic softeners, or mechanically with combing solutions. Hemp can also be blended with other fabrics to get the required characteristics.
Hemp hurds can be wet-mixed with lime to make a concrete alternative, sometimes dubbed 'hempcrete' – a non-toxic, airtight, vapour-permeable material with strong thermal performance. Hemp-based concrete can be used to make walls, floors and roofs, usually with a sustainable timber frame. Traditional cement is responsible for 8% of all global greenhouse gas emissions, while hempcrete is a better-than-zero-carbon material, locking away carbon in the bricks during the lifetime of the building.
Hemp can also capture twice as much atmospheric carbon as forests.
Paper was first made from hemp over 2,000 years ago in China and it is enjoying a resurgence in popularity today, as it offers higher strength and tear resistance, reduced discolouration and ageing, as well as significant environmental benefits. Hemp is faster-growing than wood with higher yields, requires fewer chemicals for processing, and can be recycled many times more.
Hemp can be converted into a biofuel for heating, electricity generation, and transportation too. A 1941 prototype Model T from Henry Ford was not only partly-made with hemp, but also designed to run on hemp-based ethanol fuel.
Hemp can also be used as the basis for food and beverages. As with other nut and seed-based dairy alternatives, hemp milk is made by blending water and hemp seeds. The seeds can also be used to make oils, butters and cheeses.

KEY FACTS:

2x

Hemp can capture twice as much atmospheric carbon as forests

$824mn

The total value of hemp grown in or under the protection of the US has risen drastically, reaching USD 824 million in 2021

0.3%

By law in the US and Canada, hemp must have no more than 0.3% THC

Key Questions to Ask:

Is hemp a controlled substance in your territory?

US laws on the cultivation and processing of hemp have been drastically loosened since the prohibitive legislation of the mid-20th century. However, growers must be licensed and have their samples tested to ensure they do not have an excessive level of the psychotropic THC. In the UK, hemp is still a controlled substance under the Misuse of Drugs Act. Jumping through regulatory hoops may add friction and expense to your supply chain.

Do you need to explain the benefits of hemp to a sceptical consumer base?

Leaving aside its associations with recreational drug use, hemp has a poor reputation as a cheap and abrasive fabric – the very opposite of a luxury garment – despite its price tag. You may need to inform your customers not only about the comparative environmental benefits of hemp, but work to shed the associations hemp has picked up in the last 70 years, when it was pushed to the margins as a restricted plant.

Will you need special facilities and infrastructure for the composting or recycling of your hemp-based products?

Untreated hemp, hemp-based papers, and some hemp plastics can be home composted. But some hemp-based bioplastics will require specific environmental conditions like ultra-high temperatures. If your hemp products are not suitable for home composting at end-of-life, a returns process for recycling or industrial composting should be made available to consumers.

Will overuse of hemp result in a negative effect on biodiversity?

Sudden increases in the popularity of raw materials can promote unsustainable agricultural practices. When grown at scale, hemp cannot be cultivated indefinitely on the same land, but must be rotated at least every seven years for the land to recover. Responsible sourcing is a must to take advantage of hemp’s environmental benefits.