Outdoor clothing brand Ternua is teaming up with colour and specialty textile chemicals provider Archroma to create a capsule collection of recycled T-shirts and sweatshirts sourced from agricultural waste from the Basque region in Spain.

The Nutcycle collection will be available in shops in February 2019, and uses dyes made from walnut shells. The region's cider houses typically serve walnuts with cider, and it is estimated that up to 55,000kg of walnuts are consumed during the season.

The fabric, a blend of post-consumer recycled cotton and polyester, is dyed in warm earthy colours using the shells collected from four nearby cider houses and then converted into dyestuff by Archroma in its Barcelona facilities.

The project is supported by the Department of the Environment of the Gipuzkoa province government, and by the province's National Cider Association.

"These are our most sustainable T-shirts and sweatshirts we have made since our creation," comments Edu Uribesalgo, group innovation and sustainability director at Ternua. "Using recycled material is one step in creating recycled clothes with a soul. Colourants from nature, on the other hand, are quite the holy grail for conscious brands."

The initiative also builds on Archroma expertise in creating its EarthColors range of plant-based dyes, sourced from up to 100% renewable resources from agriculture and herbal industries.

Earlier this year the company developed a new dye it claims provides a non-toxic way to produce the traditional indigo blue that consumers associate with denim and jeans.