"Is it ok for me to cover the top of the potting soil with wood chips (Black) like I have done with my flower bed in which these plants will hide? Or will that meess with the balance of the PH in the peat too much? "

Peat is low PH so the PH of the wood chips should not be a problem.
However, as the wood breaks down it uses nitrogen and can cause yellowing leaf and slow growth.
Just fashion a soil cover out of galvanized "hardware cloth" to stump the squirrels.

Stinky has not been online since April 2010.
Kind of worried about her.

This site has changed, look around.

Aloha, and welcome back.
Weezard