A trick to writing fresh content on a consistent basis month in and month out is to learn to look at your topic from all angles and all levels. This is beneficial for your readers, because you are creating a library of information that covers your topic inside and out. This is also beneficial SEO_wise, because you are systematically creating a collection of resources that covers your subject backwards and forwards. This creates a greater chance of your article turning up for searches on every aspect of your niche. Last but not least__learning to cover your topic from all angles and all levels of depth is beneficial for YOU, because it forces you to establish your expertise in your field. If you are not already an expert in your field when you start writing articles, you surely will be after a year of consistently writing articles on every conceivable angle of your topic each month.
I'd like to give you an example: I recently wrote an article outlining several ways to get out of a writing slump. As I was writing that article, I came up with about 7 or so ideas for getting your brain out of a creative rut with your articles, including some article template ideas and some writing productivity techniques. I submitted the article, and then thought__ "Each of those ideas for getting out of a writing slump needs to be elaborated on and explained further. I can do a new article for each idea." And so I did__so far I've bounced 4 or 5 articles off of that first article, and I have even more ideas that I've gotten from that first article that I haven't written about yet.