I am currently making a BUNCH of royal icing flowers for a bday cake I'm doing. I have no idea how many I need to make and would like to make other ones anyway to have on hand for future cakes. My question is... after royal icing flowers have been made and allowed to dry and harden... can I store them in the freezer? I'm assuming I don't NEED to... but it would be handy if I could. Will the moisture ruin them when thawed?
Just keep them carefully packed in a box in a dry, dark place. Humidity will ruin them, so don't keep them in the freezer. Sunlight (or other light) can fade colors. Properly stored, they should last for long time (6 months to a year)
I would avoid the freezer. If they get condensation on them, they will start to melt.
If they are dry really, really well you can store them in plastic container, but if they aren't dried totally, that can cause problems. Also if you do that you want to store it with something that would absorb moisture.
Best bet is a cardboard box, so that the flowers can 'breathe'.
I keep mine in a flat little cardboard cakebox. They keep VERY well like this if you keep them dry. No fridge!