On Aug 11, 8:35 pm, "YMC" wrote:
what about grass seeds and runners? apparently the compost isn't hot enought
to kill them; my old gardener refuses to put the lawn mower clippings into
the compost for this reason.

My compost heap is usually 50-80% grass clippings. If I didn't use
grass I'd be waiting a year just to get enough organic waste. It heats
up very quickly and if turned regularly seems to get hot enough to
kill both grass/weed seeds and kikuyu and couch runners. Of course, if
you're cold composting I'm sure you'd run into problems. If you look
at the C:N ratio of grass (see:
http://compost.css.cornell.edu/OnFar...apa.taba1.html)
it's pretty close ideal if not a little high in nitrogen so its
technically a good candidate for hot composting on it's own. The main
problem I've come across when only using grass is its tendency to form
saturated, anaerobic clumps in the centre of the pile (another reason
not to cold compost them). Regular turning seems to reduce this.