Hi anyone got any tips how to make sure I have removed red spider I had in my greenhouse last year.
I can see some fine cobwebs and as the spiders are so small I dont know if this is what I am seeing
If you can afford it purchase a sulphume vaporiser . Following years of problems and trying everything on the market I now each year clear all my plants within two to three weeks.This is used by the really big horticultural companies to clear their massive greenhouses safely with no danger to the staff.
For a eight by six GH one can be found for under £100 along with sulphur by searching hydroponic stores websites.
Water does not kill red spider. I used to have a dew point propogation unit which was as wet as you can get . The red spiders loved it and multiplied like mad.
I know people say water will kill but in my experience this is another myth
Take your point Verdun.
The problem with red spider is that the hundreds of eggs are left with any method just trying to dislodge the adults, and within a few weeks they hatch and the adults are are back.
The sulphur makes the leaves acidic,which also most importantly kills all eggs.
They just shrivel up and you can see* that they are dead. Must use *visual help to see them.
In nature frost will eventually put paid to these seasonal critters.
Thank you for all your advice.
will try to keep everything damp.