An Australian backyard science experiment confirms synthetic clothing fibres do not breakdown in soil whereas within a year most natural fibres are returning to organic matter.
On 26 January, 2018, Textile Beat buried synthetic and natural fibre material swatches glued to cardboard by digging a shallow hole in relatively poor soil near a mango tree in a suburban garden in Brisbane. These were covered them with dirt and leaf litter, and occasionally watered (twice a month) until January 2019 when they were retrieved.
Range of synthetic and natural fibre swatches as buried in a Brisbane garden January 2018.
The material swatches were mostly remnants from Jane Milburn’s studio or from discarded clothing.
We were curious to confirm that synthetics are plastic-like and remain forever, while natural fibres return to nutrients and organic matter when broken down by microbes and insects in the soil.
We dug them up on January 15, 2019, and this is what we found.
Swatches of synthetic clothing materials before, left, and after being buried for one year in 2018.
Natural fibre swatches before, and after, when most were broken down or digested into organic matter.
After a year in the soil, the synthetic swatches were a little grubby but effectively unchanged.
However, the natural fibre materials had mostly disintegrated or disappeared, particularly the wool and cotton fibres, and we could only retrieve some swatches of silk and hemp. Silk is a protein fibre and tightly spun (and this coloured piece is particularly coarse) while the lignin in hemp makes it slower to breakdown into organic matter.
All the synthetics remain as they were and did not break down when exposed to the elements. That could be a good thing if you planned to hold onto and wear garments for a very long time, which most people do not.
Almost all the natural fibre swatches disintegrated within the 12 months and we could not even find remnants. The silk (particularly the coarse woven piece) and the hemp swatches are the most visible. I am not convinced the leather would have disintegrated completely but it could not be found.
The results are not a surprise because soil researchers bury cotton undies to reflect soil heath with the #soilyourundies campaign and the Campaign for Wool buried wool and synthetic jumpers a few years ago and found similar outcomes.
(Note: one synthetic swatch, perhaps a blended fibre, may have undergone a colour change and been mis-placed with the natural fibres in ‘after’ photo. The craft glue remained visible, while most of the cardboard had also disintegrated.) #naturalfibres #wool #cotton #syntheticfibres #soils #clothingfibres #backyardscience #slowclothing #slowfashion #sustainablefashion #eco #plastic