Should I used colored frosting to crumb my cake or white?

[Super Salad]

I will be crumbing a large sheet cake (1/2 chocolate and 1/2 yellow) tomorrow evening. The cake will ultimately be frosted w/light green buttercream and am wondering if I need to color my frosting before I crumb if can wait until I actually frost it. I kind of expect it won't matter but thought I would ask.

[sarah galvin]

I have always coloured my icing before crumbing. I think you would have a richer, deeper colour if you also crumb with the tinted icing.

[Super Salad]

thanks!