Something for people to try, using coffee grounds as a growing medium.

The earth out the front of my place, along the sidewalk is rubbish. Very dry
and powdery. It had all manner of weeds and crap grasses in it that kept
seeding in to my lawn. Late summer I knocked it all back and mulches across
it with used coffee grounds to add (free) organic matters. About 2 months
later I have seeded grass in to it after a good raking. The grass is doing
very nicely.

I am seeing whether mustard seed will now grow in a bed of used coffee
grounds.