I have students who have problems with dry icing the the crackly edges when they make roses. I tell them to add corn syrup to make it creamier, but sometimes they still have the edges. Is there anything else you can add or do to get rid of the edges?

if the cracking edge is from the pointed edge of the rose tip you need to open the tip up a little. Also piping slower helps

and if their icing is too stiff it will always crack even with corn syrup.....a little piping gel helps too........unless their icing is too thick

Instead of &/or in addition add a bit more fat (Crisco/butter or?) to make it creamier.

Beginners have a problem w/the edges cracking because they are not turning the nail fast enough. It's a common problem
BTW: I *love!* roses w/cracked edges