Experimenting with nettle for fiber
Urtica dioica, commonly known as stinging nettle or common nettle (eesti keeles kõrvenõges), is a widely spread plant in Estonia and throughout Europe. Nettle contains fine bast fibers that have historically earned it the nickname “Silk of the North” (Põhjamaa siid).
Unlike flax or hemp, which require cultivation, nettles grow wild and abundantly. This made them a natural starting point for my experiments with local bast fibers. All I had to do was step outside and harvest the plants growing along my fence.
While nettles are easy to find, processing them is far more complex. Compared to flax, nettle stems contain significantly more pectin, which binds the fibers tightly to the woody core. The fibers themselves are also shorter, which, combined with the high pectin content, makes processing both time-consuming and labor-intensive.
My early experiments with nettle were not particularly successful. However, as I became more familiar with the plant’s characteristics, my methods gradually improved.
In general, nettles can be processed using techniques similar to those used for flax and hemp. So far, I have tested five different methods to extract usable fiber material.
Making cordage from fresh nettles
You can get really interesting material by simply peeling the outer layer off the wooden inside, separating the fiber bundles into thinner strips and spinning them into two-ply cordage.
This process is relatively easy, because you don't have to get rid of the green plant material. At the same time, if you do it carefully, you can get quite strong cordage.
However, after drying, the cordage turns brown and might not be very flexible, but i think it is a lovely way to get to know nettles and find out where the fiber is.
Processing fresh nettles
I have managed to get good results from processing fresh nettles. I begin with peeling the green outer layer off the stems. Then I separate the fiber bundles into thinner strips and leave them to dry for 24h.
Next day, I rub the fiber containing strips by hand to make the plant material softer. After that with the help of a butter knife or a hand carder I can get most of the plant material off the fibers.
As a result I have beautiful green and soft fibers. After getting sunlight the fibers turn natural white.
Dew retting
Retting is a process where harvested nettle stalks are spread evenly on the ground, where natural process including bacteria, sun, air and dew produces fermentation, dissolving most of the stem material surrounding the fibre bundles. Within two to three weeks, depending upon climatic conditions, the fibre can be separated.
This method works well when you don't accidentaly leave the stalks retting for too long. When this happens, the fibers get damaged by the bacteria and will eventually brake.
Timing is very important here.
Water retting
This method hasn't been very successful for me, because it is very easy to over ret the stems. Retting process happens faster in water, therefore it is possible that I have left the nettles in water for too long.
The fibers get damaged easily and brake when left in water for too long. You can see the soft white fibers coming out of the stem after retting in water.
However, the water used for retting nettles is very useful in the garden. It has a strong smell, so you might not like the liquid, but it repels insects from berry bushes and is good for the soil.
Boiling in wood ash
When adding water to wood ash it creates lye which can be used for getting rid of the plant material around the fibers.
I conducted an experiment where I took the stripped fiber bundles, winded them into nests, sinked them into lye from wood ash and boiled the material for 3 hours.
After boiling, I took the fiber nests out and washed them in water. The green plant material came off very easily. The lye had also eaten away all the pectin holding the fiber bundles together resulting in very short fibers.
After drying, the fibers needed rubbing and combing to get soft again.
Conclusion
I have to mention that a very important component in a successful nettle fiber precessing is correct timing. Nettle stalks usually start to contain fibers after they have produced seeds, which happens here in the beginning of June. In my experience, June and the beginning of July is the best time for fiber processing, because then the fiber containing outer layer peels off the woody inside more easily. This means that the stems are wet and it is easier to separate the fibers. I have experienced that at the end of July and in August the nettle stems are dry and strong which makes it more difficult to separate the fibers. It is reasonable to make the laborous work easier with a correct timing.
For retting, it is also better to use nettle stems picked in July the latest, because then the fibers are better quality and the plants have less damage from insects.
When talking about hand-processing, I really like the fresh nettle processing method I described earlier. I also like to leave some plant material in the fibers so that they hold together making it possible to get longer fibers. This way you can see that this is a material from nature and the nonstandardness is precious.
Industrial production of European nettle
While ramie (another plant in the nettle family and native to eastern Asia) is more commonly used for textiles, stinging nettle is more rare.
I have located one factory in Germany that produces fiber from locally grown stinging nettle. I managed to get a sample from their production which I can share here. The fibers are white and shiny but at the same time very short and slippery. This means that right now, it is not possible to make yarn 100% nettle. Nettle fiber is combined with cotton, hemp or both.
Nevertheless, nettle has very good properties such as high breathability and tensile strength, the fibers are absorbent, antimicrobial and antibacterial. The mixed yarn is woven into fabric, which has these good qualities.