Answer:
I am the only vegetable or fruit that is never sold frozen canned processed or in any other form but fresh.
Searing 'cross the pitch-black skies I scream in celebration Yet moments later my outburst through I am naught but imagination.
I have no voice but I can teach you all there is to know. I have spines and hinges but I am not a door. Once I've told you all, I cannot tell you more. What am I?
I fly to any foreign parts assisted by my spreading wings. My body holds an hundred hearts Nay I will tell you stranger things when I am not in haste I ride and then I mend my pace anon.
I am in the middle of water but am not an island.
Black we are and much admired. Many seek us if they are tired. We tire the horse, and comfort man, and turn White when we've fulfilled your plan.