How to ask an awkward question?

ok so i write a monthly column for a local newspaper,in the beginning i approached the editor with a draft on the specific subject of the column, was petrified that would seem to confident but it worked out and he put it in the paper, however nothing was said of payment and i don't know how to broach the subject? im afraid that he might tell me to just not do it anymore? obviously at the time i was so grateful that i got the opportunity i didn't think about the money! any ideas?