In article ,
says...
Does anyone know if Roundup (diluted and undiluted) or Verdone has a
shelf life, if so what? I was thinking that buying large quantities is
cheaper, but no if it becomes ineffective after a while.

I bought a container of concentrated Round up when we arrived here in
1982 and I have just mixed the last up it works just as well now as then,
I also always mix a 5 litre batch but use only very small quantities in a
hand mister for those awkawd weeds so once mixed it also lasts 1-2 years
with no reduction in effectiveness.
What it says on the packaging I am afraid I have no idea!
--
Charlie Pridham, Gardening in Cornwall
www.roselandhouse.co.uk
Holders of national collections of Clematis viticella cultivars and
Lapageria rosea