That's a phrase you might be hearing soon, if an Italian alternative clothing manufacturer has anything to say about it. Corpo Novo uses stinging nettles (Urtica dioica) as their fiber, and for good reasons:

Nettle fibre had previously been used to clothe Napoleon's Armada and was reintroduced during cotton shortages during both world wars:

"The fibres of the stinging nettle have a special characteristic in the fact that they are hollow which means they can accumulate air inside thus creating a natural insulation. To create a cool fibre for Summer the yarn lengths are twisted closing the hollow core and reducing insulation. In Winter with a low twist the hollow fibre remains open maintaining a constant temperature.

"Existing problems in the agricultural sector such as overproduction in the dairy industry, over-fertilisation of the soil, problems due to monocultures as well as the lack of financial opportunities underline the need for alternative crops. The stinging nettle is a perennial plant which thrives on nitrogenous and over-fertilised soil, making it a very interesting alternative that would add a completely new aspect to agriculture in central Europe."

Thanks to the good folks at World Changing for the link!