I have done 2 Belgian Wit beers and they had Orange Peel (Bitter & Dried) and Coriander as part of the ingredient list. I would think that you might be able to add some lemon zest to the secondary to add some flavour, but I am to much of a NOOB (as we are called) to make that call for certain.
I am sure someone with loads of experience will post a response to your ???.