Commonly known as ‘soft’ fibres, bast fibres are the fine, flexible fibres obtained from the stems of dicotyledonous plants.

Bast fibres have been used to manufacture ropes, sacks, sails, and other industrial fabrics for hundreds of years. Commonly known as ‘soft’ fibres, bast fibres are the fine, flexible fibres obtained from the stems of dicotyledonous plants. A sustainable choice, bast fibres support regenerative agricultural practices that can help the soil sequester carbon and as a natural resource, are entirely biodegradable. In this article we will investigate four of the most utilised bast fibres: flax, hemp, ramie, and jute.

Between the epidermis (the outermost layer of cells) and the core of the plant’s stems are soft, woody fibre bundles or strands which can be over one metre long. The strands are composed of individual filaments made up of cellulose and hemicellulose cells bonded together by pectin or lignin, a cohesive gum which strengthens the stem of the plant. 

During harvest the stems are cut close to the ground and the fibres are separated either through a natural decomposition process called retting (engaging moisture and bacteria to rot away the gummy cellular tissues) or by decortication (peeling the stems manually or mechanically). After retting, the fibres can be mechanically extracted through a process known as scutching. 

In contrast to bast fibres, leaf fibres are obtained from the leaves of monocotyledonous plants with parallel-veined leaves, such as grasses, lilies, orchids, and palms. The long, stiff fibres of plants including abaca, cantala, Mauritius hemp, and sisal are generally used to create cordage or ropes, however, due to labour-intensive harvesting processes they are used less frequently than synthetic options.

Flax (Linen): Famously grown across northern France, Belgium, the Netherlands, and Ireland, flax is the most popular and strongest of the bast fibres. Wild flax fibres found in the Upper Palaeolithic layers of a Georgian cave indicate that humans have been crafting cords and weaving flax baskets for over 30,000 years. 

Undyed flax ranges in colour from ivory to shades of tan and grey and is not only 2-3x stronger than cotton but also considerably better for the environment. Flax is considered a low-impact crop as it is resistant to pests, negating the need for pesticide sprays, responds well to traditional farming techniques including rotating crop and leaving fields to fallow, and draws carbon into the soil. 

Jute: Jute, also known as hessian, has long, shiny fibres suitable for spinning into threads and is second only to cotton in the quantity produced and the array of uses. Native to tropical and sub-tropical environments such as India, jute enjoys the rainy season and was long considered the ‘golden fibre’ in Bangladesh not only for its colouring but due to its generation of foreign trade. 

After suffering competition from synthetic alternatives in the 1980s, global environmental awareness has replenished demand for the biodegradable fibre, and it is being crafted into bags, carpets, textiles, and insulation materials.  

Hemp: An historically important fibre, 80% of global fabric production in the 19th century was hemp and with sustainability front of mind for many producers and consumers, it has regained popularity as a strong, long-lasting, environmentally friendly fibre.   

Naturally occurring in shades of yellow, green, or brown specialist processes are required to produce a whitish colour and lustre similar to linen in look and feel. Hemp is exceptionally water resistant and blends well with other fibres such as cotton to create textiles. An incredibly multi-purpose fibre, hemp can also be used to create a variety of products including shoes, bioplastics, and as an alternative to fibreglass insulation and concrete. 

Ramie: Native to Eastern Asia, ramie has been cultivated for centuries in China and is now also grown in Brazil. The stiffest of the bast fibres, Ramie is an herbaceous perennial in the nettle family which can be harvested 3-6 times per year for 7-20 years.  

Ramie has the longest of the bast fibres and is naturally a luminous white colour and is known for its excellent abrasion resistance and tensile strength (3-5x greater than cotton and 2x greater than flax) although it is unfortunately brittle and will break if repeatedly folded in the same place. Ramie is often mistaken for linen due to similar properties in absorbance, quick drying, and resistance to bacteria.  

In China ramie is frequently blended with cotton, wool, and silk as an affordable alternative to linen and remains a popular choice for heavy duty textiles such as canvas, packaging materials, and upholstery. 

Thanks James Dunlop for this interesting information.