Probably the same way I prospect a ton of ore.
I make a macro for each ore or herb type. For example
I then ensure the toon only have even stacks of 5 of each ore and herb, then place the macro on my DK spam bar.Code:#showtooltip Twilight Jasmine
/cast Milling
/use Twilight Jasmine
So while I play my DKs, my scribe / prospector is working away :)