I am not too sure about his fav flowers, I would say narcissus because of the myth of a man who fell in love with himself but maybe that's more association

As of his fav meals he loves porchetta which is a way of cooking pork that it's really good and very common in Rome, it's also pretty ancient as well, I also think he would be fond of puls which is a kind of polenta (porridge) that was very common in ancient Rome