Explain aphid control paragraph for me please?

 

This is from the Crocus web site, on aphid control. I've read this a number
of times and I have finally concluded that I *really* do not understand what
it means. The first two sentences are clear enough- it's when they go on to
nettles and "a colony" (of what?) that I get lost. And then cutting back the
nettles- why? Nothing of the last two sentences seems to make sense. Maybe
I'm just having a very dense day, or possibly this is not explained as well
as it might be. Please- could anyone explain the last part to me?


Organic - the best thing to do is encourage the predators of aphids, such as
ladybirds, lacewings and hoverflies, into your garden. This can be done by
planting nectar-rich flowering plants which attract them, such as buddleia,
calendula, sedum, stocks, sweet William and wallflowers. [That's clear
enough, but from here on I'm lost...] Get a head start on the aphids by
growing a patch of nettles with a small colony to help build up natural
predators in your garden. Cut back the nettles when aphids appear in other
parts of your garden to encourage the predators to seek them out.

--
VX (remove alcohol for email)

 


I agree it's not very clear, but I would read this as suggesting growing
nettles for a crop of aphids (eating the nettles) to act as a food
source for aphid predators. When aphids appear on other plants chop down
the nettles, and the predators have lost their food supply, and will
have to look elsewhere (the other plants).  (Different types of aphids
eat different types of plants.) What puzzles me is how one guarantees
the presence of aphids on the nettles.
--
Stewart Robert Hinsley

 



buddleia,

changing the subject slightly, I have been spraying aphids and thrip on
roses for some weeks with a watered down liquid manure. It takes 2-3
applications to wipe the population out but seems very effective. Soapy
water may do the same job or the manure may contain something else a little
bit special. The roses also get a good foliar feed at the same time however.
Even better the smell of the liquid manure gives my wife something to
complain about.

rob

 



could anyone explain the last part to me?

...

Nettles act as host to aphids in the Spring before other any
other plants, and when there is little other food around for
ladybirds. Without a steady supply of food throughout both
Spring and Summer ladybird numbers will be reduced. By Summer
when other aphid hosts are in full growth the netteles
can be cut back to encourage the ladybirds to move on to
those.


michael adams



buddleia,

 


Some biocontrol companies sell 'Banker Plants Kits' which are basically
aphid
infested plants (usually oats), in which you can build up natural
enemies for
later release.  The favoured option by many folk now is to
use a safe foliar
treatment (such as savona, sb plant invigorator or
Just Bug Killer), when aphids
first appear then add beneficials to keep
future ingressions in check.


--
Pest Effects