Sorry it should have been "cotton". Didn't edit too well.

mimidi,
cotton lint should be used instead of lint from polyester as the polyester hold moisture. The cotton lint will breath and dry if it gets wet. Also dog and cat fur can be used as well as people hair and cotton threads. Put the nesting material inside a suet cage or one of those mesh onion bags and all the birds not just hummer will pick at it.

Penny

I knew there was something that shouldn't be used I just could not remember what it was.