If it's not a tree or a flower, then I call it a plant. I know that isn't accurate especially when I include mushrooms in the lot. So yes, the plant category on this site is a bit of a catchall.
There's no arguing that plants are going to be easier to take a photo off than any animal simply because a plant isn't going to run away. However, just because it's easy doesn't mean that a plant photo is going to be worth taking. The shots below appealed to me for various reasons. Either the lighting was good or I thought I had an opportunity to frame the plant in an interesting way. I hope at least one of them appeals to you.
Three of the plant pictures are of fungus because they look unusual to me. They're the aliens of the plant world. Three of the other shots are of plants from Joshua Tree National park. And the one remaining image is a closeup of some really healthy looking moss.