Tim W wrote:
"Stuart Noble" wrote in message
om...
Tim W wrote:
"Carryduff" wrote in message
...

I would like to re-use last years compost from my raised beds ....

... The old compost will be gradually reduced by continuing decomposition

But what does it decompose into? Seems a pointless discussion unless one
knows what it consisted of originally and what it becomes when it rots
down. How does decomposed B&Q compost differ from any other rotted
vegetable material?

I grew a bumper crop of spuds in nothing but said compost, which
supposedly has very limited nutrients. Over a period of a few months the
"compost" broke down to a fine powder, which went on to support various
flowers without the need for further nutrients.

I think maybe it's time someone defined the term "compost". Is it the
semi-rotted tree bark you buy in B&Q or the stuff that comes out of your
compost bin? It surely can't be both


I am no biochemist but I guess it is the standard reaction of hydrocarbons
plus oxygen turns to water and carbon dioxide shedding a little energy in
the process and I would guess it is done with the assistance of all kinds of
micro organisms, fungi and small animals.

Tim W



But don't you think maybe we're being conned? The general purpose peat
free compost from B&Q etc, which we are encouraged to think of as
exhausted of nutrients after a few weeks, must surely decompose, like
any other vegetable material, into useful nutrients. Perhaps it doesn't
provide a complete range though. Dunno, I'm not a chemist either.