I had some mold forming on a couple of cuttings... it wasn't too severe, so I used a Q-tip and put some copper fungicide on the exposed parts of the cutting that showed the mold.  The copper fungicide is 7% copper sulfate in dust form.  It seems to have worked for getting rid of the mold, though the dust also had a "shriveling" effect on any tender green tissue (topically, in the places where the dust was directly on the tissue... didn't observably bother other green growth that the dust didn't contact directly).  So cuttings that had mold on new stems, I snipped off the new stems and just put a very light bit of dust on the cut end.  Those cuttings are doing great now.  They've got roots and new top growth... they seem to be thriving and healthy with no observable mold.

But some of the others were tip cuttings and had no top growth yet when I noticed the mold.  I applied the dust to the tips.  The mold seems to be gone, and they've now got roots.  (The roots came after the mold went).  I'm thinking the copper sulfate dust is inhibiting top growth on those tips, so I'd like to remove the dust.  But how?  I thought about just pouring water over it to try rinsing it off, but I'm not sure that'll be effective... the cuttings are in cups with perlite (so it's not easy to rinse, without the rinse flowing into the perlite around the roots).  Here are a couple of questions:
   a) will just rinsing with fresh water get this dust off effectively?
   b) if I rinse them and the copper sulfate rinses down into the root zone, will that harm the tender new roots?
   c) is my inference that the copper dust inhibits green growth a correct one?  Based on observation it looks that way to me...  but I'm unsure whether it'd be better to just leave the dust on or try to get it off... this set of cuttings have roots now but there's no top growth yet.  Does copper sulfate inhibit green top growth locally/topically applied?
   d) Anyone have any knowledge or suggestion?

Mike   central NY state, zone 5

I wasn't seeing any advice here on this forum, but elsewhere found this article:
http://homeguides.sfgate.com/effects-copper-sulfate-plants-27633.html

And this one with more precise information about the actions of copper sulfate:
http://pmep.cce.cornell.edu/profiles/extoxnet/carbaryl-dicrotophos/copper-sulfate-ext.html

And this one about field crop effects:
http://www.uwex.edu/ces/crops/CopperSulfate.htm

I'm still unsure how to remove it, but on one of the cuttings I'm attempting to "wash it".   I am hoping to do this without having to remove the cutting from the cup of perlite/promix, because the roots are so tender still that I'm fearful of breaking them off.  So instead I'm using tape to secure the top of the perlite and will try rinsing with water from a small spray nozzle, holding the cup sideways.  But I'm just trying one for now.

If anyone on here has advice or experience with this sort of thing, I'm still interested to hear your advice.  Some of these cuttings are varieties that I have only one cutting of, so advice would be appreciated on how to save them.

Mike   central NY state, zone 5

Sorry , no advise, have never used it.
But wanted to wish you Good luck.