I have a lived-in car. It looks like it's been places, done stuff. If it was a face, you'd say it had character, or was evidence of well-lived life. As an appliance, it's both well-used, and well useful; and look, here is another use: plant pot!
That little volume, under the door, had gathered a soft mulch of vegetable matter over the years, and into it, a seed had washed, and the warmth and light of spring sunshine seeping through the gaps around the door had sparked germination.
It's a little early to tell, but I sense the limitless ambition of a tree seedling.
It seemed a bit mean just to cast is aside, so I hoiked it out and popped it in a pot and promptly forgot where I had put it. Hopefully somewhere more convenient for a tree to be than caught in the bodywork of a Nissan Micra.