In my experience it can take forever. Some worms will migrate; many will not. I've tried this method and even 6 months later found many hundreds of worms in the side that is not being fed. However, I believe other people's worms do migrate as advertised. If anyone has a theory why it works for some and not others, I would love to hear it!

Good luck with yours!

I have had most of the worms in a 4 ft. x 4 ft bed go from one corner to the next overnight when I feed in a different place than before. That is usually when the bed is just about done as far as any bedding still being the original material I put in it. If you still have good eatable bedding their would be no reason to move.

I've found it depends on how "done" the old bedding/food is. I harvest every four-six months. At six months, I only see about five worms or so. At four I see more. But most have migrated.