Good Morning.

I am making a wedding cake, due tomorrow. The cakes are frosted in buttercream. Here is a picture of the cake I'm copying....

https://www.pinterest.com/pin/143270831874149143/

I'm not doing the flowers the way they are in the picture, I made them out of wafer paper. I made the "medallions" out of royal icing.

My questions are these: The cakes were frosted yesterday and in the fridge all night. Should I take them out and bring them to room temp before decorating? What should I use to "glue" the flowers and medallions to the sides of the cakes? I have royal icing, buttercream and edible glue. Once the cakes are decorated, can they go back in the fridge until I deliver tomorrow? The buttercream has butter in it.

Thank you so much for helping me work this out.

Stay Sweet! Christina

Unfortunately, this is a really good example of how changing from fondant to buttercream and from fondant to royal icing and from gumpaste to wafer paper isn't always the best idea.

Wafer paper flowers are really unpredictable with humidity, so I wouldn't put them in the fridge unless you're sure they won't melt and sag when you take it back out. I don't know what the humidity is like where you live, but I wouldn't use wafer paper flowers on a cake unless I put them on at the reception site due to humidity and having to keep the cake refrigerated until it's delivered. If you're putting them on buttercream they can absorb the oils in the icing, which will take a while to do, but might soften them up.

For the royal icing plaques, you might be better off sticking those on at the last minute too. If you were attaching them to fondant you could use royal icing, but if they're going on buttercream it's probably best to use more buttercream to stick them on the cake. However, buttercream will break down the royal icing after a while also, so that's also something you should do last-minute. Again, it will happen slowly, but the plaques are going to soften up if they're on buttercream.

If it was me, I would make the plaques out of fondant and attach them with buttercream, then put the flowers on the cake when I delivered it. Otherwise you'll be taking a chance that refrigerating the cake after you decorate it will affect the flowers and the plaques.

Ok.   I put one of the wafer paper flowers on the butter cream a few days ago. I did not put it in the refrigerator and just left it on the kitchen cabinet. Th wafer paper did not seem to be affected at all by the buttercream.  So what if I decorated The cake  today and just left it out of the refrigerator.  

Then you have to deliver it when it isn't cold, which is risky in itself. The paper will be more affected by the changes in humidity in and out of the fridge, honestly. If I had to do this cake in the configuration you're doing it, I'd refrigerate it tonight, then a couple of hours before delivery take it out of the fridge and put the plaques on it, then stick it back in the fridge. When it came out I'd deliver it and attach the flowers during setup using some buttercream on the ones on the cake. The other ones look like you could just put them in little bunches and stick them on the cake when you get to the venue.

With all the wafer paper trendiness I was curious about outdoor weddings, and after looking at the weather and humidity levels in San Diego where Stevi Auble is (she does the cakes that are basically all wafer paper decorated) it's very low humidity compared to where I am. I put some wafer paper flowers outside on my porch one day to see what would happen, and this is what happened. http://acaketorememberva.blogspot.com/2014/10/wafer-paper-and-humidity-dont-mix.html

I'm afraid to mess with the fridge and take a chance on it, but depending on how you made the flowers and how thick they are they might hold up better than some that had really thin petals.

Thank you Costmeczar for you great advice!