Question
i dried some roses and a couple of them seem to have a cotton-like mold (?) between the petals... is there any way to save them/clean it or should i just throw them away?  and if it's the latter, do i need to throw them all away or just those with the 'cotton'?

Answer
It depends on how you dried your roses. If they were done by silica sand, then the problem is simply that they weren't left long enough in the sand. However if they were air dried, it usually take at least three weeks to make sure they are dried out completely. Because if they aren't then mould will occur or even tiny insects will make their home in them. It would be wise to just throw the ones that have the mould out as it could possibly get worse. Hope this helps.