Getting Moss on Rocks Was Tobacco/Airstrike
One thing that helps is to get some moss of the sort you would like to grow
and put in a blender with the buttermilk and blend the two together.
Some people also have good luck with a milk/yogurt/moss mix.
This makes it easier to get moss started over the whole surface.
It may help to mist the rocks regularly in the shade and also to locate them
somewhere that the buttermilk mix won't get washed off in a downpour.
If you can't keep them misted regularly, try setting containers of water
near them so that water can evaporate by them. Be sure all the water is
completely emptied on a regular basis so that mosquitos can't finish
a hatching cycle.
community_garden maillist - email@example.com