"Do y'all think the bermuda will be a problem?"

Bermuda is the most evasive grass there is. One can apply glyphosate (RoundUp) when bermuda is dormant to kill weeds within the grass and still it survives - often coming back with a vengeance.

The problem with bermuda is not only does it have stolens above ground (runners) but also rhizomes below the ground which are difficult, if not impossible, to eradicate.

Good luck - Bermuda is called "devil's grass" for a reason, LOL!

I would dig a trench about two ft deep and staple the weed blocker vertically around the parameter of your RB box. That would give free access to your bedding to the red worms, which you want. In the center of the box, use as much paper-cardboard as you want, the red worms will have it for lunch and by that time it will be too late for the weed seeds.

John

Here is a link that might be useful: Johns Journal