Why are some hemp fabrics blended with cotton?
Hemp has 3 times the tensile strength than cotton, it is a hollow fibre so has anti-bacterial properties and obviously all its eco-credentials.
But, it is also a stiffer fibre, and unless heavily processed, it feels quite rough compared to cotton, so the first reason is to soften the fabric a bit. Hemp does soften over time with washing and wearing, but blending it with cotton, and we mostly use organic, enables us to allow that process to happen naturally with wearing and washing rather than use processing first. The classic saying is that "hemp wears in, not out".
Where it is not so much of an issue like in jeans, bags and jackets, we use 100% hemp.
The 2nd reason is cost. Due to economies of scale and supply issues, cotton is MUCH cheaper than hemp, so hemp cotton blends are cheaper until we have a s much hemp being grown and processed on the planet as cotton (we have some way to go), hemp will have a higher price. Already we get told that are stuff is too "expensive", so we would lose a lot more customers if we had to increase the price of our garments by 30-40% if everything was 100% hemp. People still do not realise the difference between price and cost. Read the blog here: http://www.hemporium.com/blog.php?article=39
Another reason that 100% hemp has a higher price is due to the fibre structure. Hemp has very long fibres, and very short fibres. Due to the mechanical processing to extract the long fibres unbroken, these are highly prized and go into high value textiles. The shorter fibres are more abundant and have similar properties, but not easy to spin, so they are blended with cotton fibres and put through traditional cotton spinning machinery to be made into yarn, producing an affordable textile that has the strength, insulation, breathability and anti-bacterial properties of hemp and the softness and cost competitiveness of cotton.