On 11/26/2011 1:21 PM, Frank J Warner wrote:
I have about a gallon of premixed Roundup in a two-gallon garden
pressure sprayer that I mixed about six months ago and did not use. It
has been sitting in my garden shed since June.
....
It's no biggie to mix up a fresh batch, but as expensive as this stuff
is, I'd like to not waste it if it's still good. I thought I'd ask here
before calling Monsanto.
....

It'll be ok...just wet a little more than normal.

We use it in large quantities (like 55 gal drums) for ag purposes and
often may have some left from one season to next. It's not quite as
effective even then but for a couple months or so doubt if you'll see
any difference.

Oh...throw a little household detergent in there as a surfactant...it'll
wet better that'll help.

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