Thought I would share my experiences of using coffee grounds as a lawn fertiliser this last spring.
Summer has (nigh on/almost/perhaps) arrived and almost drawn my 3 1/2 month experiment using coffee grounds as a lawn fertiliser to a close. All in all I am quite pleased with the results.
My front lawn was looking very nice last autumn, until I accidently scalped it with a reel mower however. It never recovered in time before winter and had a infestation of moss over the cold months. The back lawn was not quite so nice but was coming along well in autumn and didn't get scalped.
The grass is a mixture of fescue, rye and bent grass (brown top), cool season grasses so over spring they grew well and are starting to slow down with hotter weather appearing. Every week I get about 50 litres of used grounds from a local cafe.
Once I had gotten the moss under control I started spreading the coffee grounds on the lawn. To cover the entire lawn was about a 4-5 week cycle. I tried to apply them a day or 2 before rain so they would dry on the surface and be washed in by rainfall. I combined this with mulching the lawn (not using a catcher) and gradually lifting the blade height through spring.
The combination of the 3 has resulted in a very nice lush lawn with the added bonus that the grasses, given the height of mowing, have been able to self seed in places. All is still not quite right on the front lawn. There are some bald patches I will have to oversow in autumn and I have yellow clover (a spreading mat type clover that smothers out grasses) in it at the moment. All in all however I have found using coffee grounds, mulching and higher mowing beneficial.
As an aside, it is interesting to see the ebb and flow of lawn weeds through a series of years. I inherited a lawn with broadleaf weeds and alot of couch. The broadleaf and couch are all but gone but replaced by other types of weed.
rob