"Charlie Pridham" wrote in message
...

"Rupert (W.Yorkshire)" wrote in message
...

"stevesmith" wrote in message
...
Been using Vine weevil killer all year, but now found lots of grubs
eating into roots of my potted plants.

Checked on label of bottle and it says ...

This Vine Weevil Killer is a systemic insecticide to protect plants
grown in pots & containers from damage caused by vine weevils & reduce
greenfly, blackfly & whitefly infestation.
One application gives protection for up to 4 months against Vine
Weevils & helps reduce Greenfly, Blackfly & Whitefly infestation for
up to 6 weeks.
Mix 30mls with 1 litre of water & use the resulting solution to drench
the soil or compost.
Does this mean that the treatment has to be via the roots only, and
not via the leaves as per other systemic insecticides ???

Is the Nematodes more effective. Which is more cost effective, as I
have lots of pots.

Can I keep Nematodes somehow till next year.

I've used both Provado and the Nematodes.I found the nematodes
ineffective
but that may have been my impatience.
You can not store the nematodes for long periods.
The Provado is used as a soil drench and you need to make a rough
assessment
of the volume of your pot and apply the appropriate volume direct to the
soil. I believe there is a compost available that contains vine weevil
killer which may work out more cost effective.
Once you are free of the damned things grow a few primula in pots,treated
with the killer,to act as a lure.

If you are in cold parts then the bio control works well, down here it
worked well during the summer but the winter was too cold for the control
but not too cold for the vine weevils! so control was never better than
75%,
then changed to provado but found that you needed to repeat 3 times per
year
to ensure control and it was slow to apply (yes you can buy ready mixed
compost but it has a short shelf life) we now use Vi nil which is
excellent
but very expensive and I am not sure if it is available to gardeners.

--
Charlie, gardening in Cornwall.
http://www.roselandhouse.co.uk
Holders of National Plant Collections of Clematis viticella (cvs) and
Lapageria rosea


Useful data--thanks. Do you find that plants treated with provado also seem
to have a resistance to other sap sucking blighters? I have been told that
it does have a degree of control over Red spider mite if that is ever
possible.