Does maize need any processing bebore it can be used to make popcorn/?

Answer 1

Yes. It has to be dried and removed from the cob in a certain way.

Here are 2 sites for details:
http://www.popcorn.org
http://en.wikipedia.org/wiki/Popcorn

Answer 2

Popcorn is an entirely different corn species.
If it isn't actual popcorn, the water inside is not a large enough amount to cause the kernel to pop.
You can certainly grow the popcorn...just be sure it is fully dried before popping it.