"Jeannie" wrote in message
...
"Franz Heymann" wrote in message
The
bottom line is that it is not really feasible to control pests
with a population of predators. The food supply is far too
irregular
to maintain the defending army.

Franz


I think that, while encouraging beneficial insects into your garden
may not
entirely solve your pest problems, it does help, otherwise why
wasn't the
world covered in greenfly and other pests before the advent of
insecticides.

To a first approximation it was. Why else did anybody bother to
develop insecticides? {:-))

I also think, as another contributer pointed out futher down the
thread,
that the magnitude of the pest problem entirely depends upon your
point of
view. If you want your garden to be pristine and completely free of
all
pests you will probably have to use some kind of insecticide to kill
them
and planting nettles et al will never solve your problems, if
however, you
don't mind a few green fly, and would rather not use chemicals, then
cultivating plants that encourage natural predators is beneficial to
some
extent.

As an aside, I have used this method, togther with companion
planting on my
allotment and have never had to spray with anything in 4 years,
which I
think is something of a success :-)

I would agree with that. (Or were you just lucky? {:-))

Franz