Thanks. The colour is even a little more vibrant than the picture shows (as usual).
I don't know where I read this, but I seem to remember that onion skins make a good yellow that can take some washing and sunlight without fading too quickly. I haven't tried it with cotton yet, but next time I'll stuff a cotton ball along with the other "try-out" fibers (silk, soy, alpaca & mohair this time). But I think cellulose fibers need a different mordanting to be really well dyed.
Kool-aid and other acid-dyes aside this was my first natural dying experiment. Up next (after the third onion batch) is madder, which I'm really looking forward too!
Oh, and my mum gets extra credits for saving up so many onion skins for me