I agree, I had to eradicate Starburst from my garden, it was too invasive despite freezing back every freeze. All Clerodendrons can be invasive in zone 9b, so I really wouldn't be worried about protection in 9a. I hack them all back to the ground in the Spring if they don't freeze anyway. Growing in pots the roots could freeze, in the ground the roots are protected from cold, however they send runners and could be there forever, like my bleeding heart vine and Pagoda.
