On Thu, 12 Jun 2003 01:54:33 GMT, "John"
wrote:

I just got a quote for replenishing mulch on our flower and shrub beds. It
was high enough to prompt me to look for a "permanent" solution. That's
all.
While I am on this topic, if I am to replenish with organic mulch,
which is the best kind - cedar, pine needle, etc?
Morever, what is the optimum thickness?
One quote showed 3", while the other listed 1.5-2" (and claimed anything
more was a waste).
One study I heard about at a seminar said you get increasing benefit
up to 4 inches, and beyond that it doesn't help to add more. This was
strictly in reference to trees, but I imagine the same is true for any
plant--we're really talking about doing something to/for the soil here
and the plants benefit indirectly. If you go too deep, you can create
such a big distance from soil surface to mulch surface that you would
reduce O2 penetration to roots. If you are concerned about the cost
of replenishing, you might go a little deeper than 4", since it would
probably not add as much to the cost as having to re-replenish it
sooner would, but I'd stop at 6" regardless.

Keith
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