Whilst printed organic fabrics are becoming easier and easier to come by, plain block coloured organic fabrics seem to still be as rare as hen's teeth!
However, after much searching I've finally managed to find some. If you've been struggling with the same problem, I'd recommend taking a look at the Organic Cotton Canvas section of Duckcloth's website. There you'll find 13 different shades of soft, medium-weight 100% certified organic cotton canvas coloured with eco friendly dyes. Hooray!