with flower sitting out in the open, how long does...

What do you mean, is it chopped, if it's hung right and stable reasonable conditions. It will just dry. Maybe loose some smell strength, and get a little to dry, maybe a little like chemical cough but smoke, like the effect, it would be fine, that's taking into account that bugs don't eat it on you while drying. If it's on the plant. It's only last a couple weeks over when it's done, then you are looking at many probs, midew, mold, root rot and that. Hope this helps.