The Story of Flax: Ten thousand years of Fields and fibre

Humans have been cultivating flax for at least ten thousand years. Discover the story of flax, and its importance in the Belgian economy.

In the first two weeks of June, something happens in some fields of Belgium that stops walkers in their tracks. The pastures are green. The grain is turning gold. And then, without warning, the next field is BLUE: a precise, extraordinary blue, like a piece of summer sky dropped flat onto the earth.

The blue is flax in flower. It blooms for a single day per plant, then it is over. Blink at the wrong moment and you miss it. But catch it right, and you are looking at a crop that has shaped Belgium more profoundly than almost any other. The blue fields are beautiful. The story of flax is remarkable.

The most useful plant in the world

Flax (Linum usitatissimum) takes its species name from two words meaning “very” and “useful.” It has been earning that name for a very long time. Archaeological evidence suggests that humans have been cultivating flax for at least ten thousand years. Before that, wild flax was apparently used. Traces of woven flax fibre have been found in prehistoric cave sites in Georgia dating back to around 30,000 BC.

The plant itself is slender and elegant, reaching roughly a metre in height, with small leaves and those fleeting blue flowers.

It grows quickly. The full cycle from sowing to harvest takes around a hundred days in the European climate. It prefers cool, damp conditions and well-drained soil: the precise combination that makes the coastal belt of northern France, Belgium, and the Netherlands among the finest flax-growing land on earth.

The Latin name turns out to be an understatement. Every part of the plant has value, and almost nothing is wasted. The long fibres of the stem become linen. The short fibres go to paper, composites, and insulation. The seeds yield linseed oil. The woody core (the shives) ends up in chipboard and animal bedding. The leftover meal after pressing is a protein-rich animal feed. Before modern chemistry offered alternatives for most of these applications, flax was close to indispensable.

Flanders and Flax: A two-thousand-year story

Julius Caesar, campaigning through the Low Countries in the first century BC, is said to have remarked on the quality of Flemish linen. Whether or not that account is entirely reliable, the association between this part of Europe and flax is ancient. By the medieval period it had become one of the defining economic facts of the region.

The great cloth towns of Bruges and Ypres built their wealth on wool in the twelfth and thirteenth centuries. But from the fifteenth century onwards, linen took over as the dominant textile, and with it came the spread of flax cultivation across the Flemish countryside. The turning point was the opening of the Americas. Flemish linen found an enormous new market in Spain, which needed vast quantities of fabric for trade and colonial settlement. Production surged. The industry boomed.

By the eighteenth century, flax was effectively the only industry in rural Flanders, and it was almost entirely cottage-based. There were no great factories. Instead, hundreds of small farms grew the crop, small retting pools soaked the harvested stalks, and small scutching mills beat the fibres free. The processing moved from field to farmhouse to workshop in a chain of labour that involved most of the rural population at some stage.

By 1840, 71% of households around Tielt were involved in linen production. In Meulebeke, more than 65% of the population worked in flax. The industry was not an industry so much as a way of life.

The river Leie (known in French as the Lys) became the heart of it all. The Leie’s soft, slow-moving water was exceptionally well suited to retting. This is the critical step in which harvested flax is laid in water for weeks to allow micro-organisms to break down the pectin that bonds the fibres to the woody stalk. Too little time in the water and the fibres will not separate cleanly. Too long, and they begin to rot. An experienced eye and nose was needed to judge the moment. The Leie got it right consistently, and the phrase “golden river” became attached to it, not because of its colour, but because of what it produced.

The prosperity that followed was real and visible. The merchants and mill-owners of the Leie valley built some of the finest bourgeois architecture in Belgium. The farmers of West Flanders were not wealthy, but they had work. The streets of Meulebeke, a small town that is today home to the linen weaver Libeco, one of the last great names in Belgian linen, still carry the memory of the industry in their names: Vlasstraat (Flax Street), Roterijstraat (Retting Street), Linnenstraat (Linen Street).

From field to fabric: The making of linen

Producing linen from flax is a process that has changed less than you might expect over the centuries. The steps are time-consuming, skill-dependent, and almost entirely dependent on the rhythms of weather and season.

1. The process begins with pulling. Unlike most grain crops, flax is not cut at harvest. It is pulled from the ground, roots and all, to preserve the full length of the stem fibres. Long fibres make finer, stronger linen. Cutting would sacrifice them. Machines now do the pulling, but the principle is unchanged from the age of hand-labour.
2. After pulling, the crop is laid out in the fields for retting. For several weeks, morning dew, rain, and naturally occurring microorganisms work on the stalks, dissolving the pectins and loosening the fibres. The colour of the flax shifts from green to beige. The smell is distinctive – earthy and slightly fermented. Retting is perhaps the most unpredictable step, because it depends entirely on the weather. Only an experienced hand can judge when the process is complete.
3. Once retted and dried, the flax goes to the scutching mill, where large rollers break the woody stem into fragments called shives, separating them from the long line fibres. The fibres are then hackled – drawn through thousands of fine pins to comb out the short tow fibres and align the long ones into parallel strands ready for spinning. The long fibres become the finest linen thread. The tow goes to coarser yarns, rope, and paper.
4. From there, the thread is woven into fabric. Belgian weavers developed their own distinctive styles and weights over centuries, and that accumulated knowledge of tension, density, and how to finish and dress the cloth, is part of what gives certified Belgian linen its reputation today.

Linen and Lace: The thread that connected them

There is a connection between flax and one of Belgium’s other great craft traditions that is rarely made explicit, but is absolutely fundamental: Belgian lace is, at its finest, made from linen thread. Flax and lace are not separate stories. They are the same story, told at different scales.

Before cotton became widely available in the nineteenth century, the finest Belgian lace – from the workshops of Brussels, Bruges, Mechelen, Binche, and a dozen other centres – was made exclusively from linen. And not just any linen. The best lacemakers required thread of extraordinary fineness, strength, and smoothness. It was thread so fine it was virtually invisible to the naked eye, yet strong enough to withstand thousands of crossings and twistings without breaking.

This thread came from specific parts of Flanders where the flax, the soil, the water, and the accumulated skill of the spinners combined to produce something that could not be replicated elsewhere. The lacemakers of Brussels worked in underground cellars, or in rooms with a single carefully directed source of natural light, because the thread was so fine that dry air or bright sunlight would make it brittle. The conditions were not comfortable. The product was exceptional.

Belgian lace cost more than Mechlin lace and was in high demand across Europe. Aristocrats paid more for fine Brussels lace by weight than for gold. The thread that made it was Flemish linen — the end product of those fields of blue flax

The relationship between the two crafts was symbiotic. The quality of the lace depended absolutely on the quality of the thread; the quality of the thread depended on the quality of the flax and the skill of the spinners. The collapse of the fine-thread linen industry in the nineteenth century (driven by the arrival of industrial cotton spinning) was one of the factors that eventually undermined the finest handmade lace, because the extraordinary thread it required became harder and harder to source. Today, masters of the craft report that linen thread of the historical quality is almost impossible to find commercially.

If you want to follow this thread further, you can read more in The Belgian Lace Industry: Its Rise and Fall on this blog.

Linseed oil and the Flemish Masters

Linen is not the only gift flax has given to Belgian culture. The seeds of the flax plant yield linseed oil. This is the medium that made the Flemish school of painting possible.

The technique of oil painting was developed and perfected in the fifteenth century by artists of the southern Low Countries. Jan van Eyck is the name most associated with the breakthrough, though the truth is more complex. It depended on a drying oil that could carry pigment, bind it to the panel or canvas, and cure to a hard, transparent film. Linseed oil, pressed from flax seeds, had the right properties. It dried steadily, it was clear enough not to distort colour, and when mixed with pigment it created the depth and luminosity that made Flemish painting so revolutionary.

The rich, jewel-like surfaces of van Eyck’s altarpieces, the glowing interiors of Vermeer, the warm flesh tones of Rubens, all of them owe something to a cold-pressed oil extracted from the seeds of a plant growing in Flemish fields. The great art of the Low Countries and the agricultural reality of those fields are connected at a level that is easy to overlook. They are products of the same soil and the same climate.

Today linseed oil remains a standard medium in oil painting and wood preservation. It is also, perhaps surprisingly, the main ingredient in linoleum. This is a most unglamorous of floor coverings, which is in fact a natural, biodegradable product made from linseed oil, cork dust, and wood flour pressed onto a jute backing. The name itself is a contraction of the Latin linum (flax) and oleum (oil).

Flax today: Still growing, still useful

The story of flax in Belgium did not end with the industrial revolution. It went quiet for a while, became a niche rather than a dominance, and then began to recover, quietly and significantly, in recent decades.

Belgium and France together remain among the world’s leading producers of fibre flax. The coastal belt running from Normandy to the Netherlands (the so-called flax belt) accounts for the vast majority of global fibre flax production. From 2014 to 2024, the total area under flax cultivation in the EU more than doubled, from around 80,000 to 182,000 hectares, driven by growing demand for sustainable fibres and the revival of interest in natural textiles.

The Belgian Linen™ label, created after the Second World War when weavers united to protect and promote their product, has become a worldwide quality mark. To carry it, fabric must be woven in Belgium from flax grown in the EU. Only a handful of weavers in the world are authorised to use the highest certification: the Masters of Linen designation. One of them, Libeco, still operates from the same site in Meulebeke where its mill was built more than 150 years ago. It holds a Royal Warrant from the Belgian court.

Flax is one of the most sustainable crops in agriculture. It requires no irrigation, little chemical treatment, and every part of the plant is used. It is biodegradable, renewable, and improves with age. Linen fabric gets softer and more supple with every wash.

Beyond traditional textiles, the uses of flax continue to expand. Short flax fibres can replace glass fibre in plastic composite materials. These are lighter, renewable, and without the disposal problems of glass. They are finding applications in the automotive industry and consumer goods. Insulation mats, composite furniture, and acoustic panels are other modern applications. The seeds, rich in omega-3 fatty acids, have seen a surge in demand as a health food ingredient. And linseed oil remains in active use in everything from artists’ paint to wood varnish to technical industrial products.

The plant that Julius Caesar noticed in Flemish fields two thousand years ago is still, in the fullest sense, proving to be extraordinarily useful. I hope you enjoyed this story of flax.

Denzil Walton

I created Discovering Belgium in 2011 to share the country’s hidden stories, fascinating places, and remarkable people. Through articles, photography, and audio walks, I share discoveries that reveal Belgium beyond the obvious. Hope you enjoy this site.