How do I add particles around objects In this picture, I modelled a very (bad) gravestone. What I want is described below. Would really appreciate it if you could explain it simply. I'm new to blender. Also, is there an addon for it?

I want weeds only around the stone slab not inside it (which happens if I use vertex groups



This is the best reference image I could find that resembles what I want. Notice how the grass clumps around the roadsign.
Sometimes getting out of a box is the easiest solution. I would create new object to emit those particles ;)