I have two cakes to do for the next weekend. I wanted to get as much done ahead of time as possible and was wondering about how long icing could keep in the fridge, etc. One of the cakes is going to be red velvet. I wanted to do a cream cheese frosting, but I'm worried about it sitting out when it's done, so I am just doing a plain buttercream, but the recipe I have has whipping cream in it. I know it's stable enough with the sugar to sit out for the a day or two, but how far ahead can I make it and keep it in the fridge. I'm also making a lime buttercream that doesn't have cream, but does have lime juice and wanted to know how long that would last. Thanks for all your help.

3 days is safe, thats the most ahead i ever do, always re-whip.

I don't do cream cheese frosting unless it is for a family cake that day, but for cakes for orders this is my method...

Make Icing... (whichever buttercream/cooked flour/crisco I need)
If I tint it, I Allow to sit room temperature and covered overnight first...
If I am going to use it within the next three or four days, I just refrigerate it...
If longer than that, I freeze...
I defrost the icing in the fridge...
Come to room temp and re-whip...

I know that everyone does have their own methods though... I just dont like the clutter on my counter or in my fridge more than I have to have...

If you use Earlene Moore's cr ch b'cream it can keep for something like 3 weeks. If I remember right, she has even said it doesn't even need to be frig'd at all.