Solid meats transmit heat (and some of the flavors) from the outside to the inside because it is a solid mass.
I think one problem you may be having trying to smoke a head of cabbage is that the layers of leaves are fighting against you. Each layer insulates the layers underneath from smoke and heat (and from picking up spice). Not sure how to fix that. Brining might help, but I would think that would make it a soft mess (salt and vinegar are what make cole slaw work - water drains out and cabbage becomes soft).
You might be able to get somewhere if you cut the heads in half (or quarters) put some bacon and spice on the cut sides (facing up so things drain in). Not sure it would work, but probably better than a whole head. If that doesn't do enough, you cold take the smoked pieces, chop them, and add spice/salt/vinegar and serve as a slaw or cook down as a side.
Anyway, I haven't tried any of these ideas, so I am just guessing.
If you try again, let us know how it turns out.
I think one problem you may be having trying to smoke a head of cabbage is that the layers of leaves are fighting against you. Each layer insulates the layers underneath from smoke and heat (and from picking up spice). Not sure how to fix that. Brining might help, but I would think that would make it a soft mess (salt and vinegar are what make cole slaw work - water drains out and cabbage becomes soft).
You might be able to get somewhere if you cut the heads in half (or quarters) put some bacon and spice on the cut sides (facing up so things drain in). Not sure it would work, but probably better than a whole head. If that doesn't do enough, you cold take the smoked pieces, chop them, and add spice/salt/vinegar and serve as a slaw or cook down as a side.
Anyway, I haven't tried any of these ideas, so I am just guessing.
If you try again, let us know how it turns out.