back in the day, you couldn't mix different colored plastic worms together because the colors would come off onto each other. you also had to be careful to only let your plastic lures touch "worm proof" tackle boxes or they'd "melt" the plastic. is this still the case or are modern plastics used in lures different now? i always keep my plastic lures separated and stored in worm-proof boxes and bags so i don't know. thanks.

Still the same.

I don't think it's too important with "dark" colors,

but you can't have white mixed with anything!

8-)

Still the same.

X2!  Heck yeah they do!

RW is right, it doesn't seem to matter as much with darker colors.  I recently made the mistake of putting some lighter purple and motor oil colored culprits together.  Now I have neutral greens.  Grrr..I didn't much like motor oil color anyway!

Anything red bleeds a lot.

sometimes you can make really successful colors by mixing plastics together  :

The biggest smallmouth I have seen in person was caught off the back of my boat on a "discolored" spider grub on a jighead.  It was originally watermelon but was mixed with some darker green pumpkin. It pays to be a little different even if it is on accident.

years ago, after a great day of fishing i forgot a clear plano box on the deck of my boat...only to find it a couple of days later with a glob of plastic bait inside.