I have always felt this is one of the toughest challenges here. I can manage a week- maybe two, but 30 days is a lot. I've seen people do it, and wow do I admire them. But I always wimp out and choose one subject, not one object! Good shot.
Keep it up, it is making me realise that when I do mine I will have to make sure I choose something really interesting ( I think your vase is a good choice.)