On Nov 27, 3:24*am, Steve Barker wrote:
On 11/26/2011 11:21 AM, 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.

With the glorious warm weather we're having in SoCal this weekend I
thought I'd hit a few weeds that sprouted during the recent rains, but
I don't know if this six-month-old Roundup is still good. I've read the
package instructions carefully and it says nothing about storing
premixed product. It does say that Roundup becomes inert
("deactivated") when it hits the soil, but nothing about the
effectiveness of leftover mix. I vaguely recall some of the
groundskeepers at work mentioning that mixed Roundup slowly becomes
inert with time, but my memory of those conversations is a bit fuzzy.

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.

Frank

why not just spray it and see what happens? *It doesn't go bad.

--
Steve Barker
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- Show quoted text -

I've mixed it and had it sitting for months in a hot garage and
it worked fine. Also, I have 3 gallons of the high concentration
glyphosate, ie generic Roundup, that I've been slowly using for
10 years and it works fine. Roundup comes in a variety of
concentrations and I would strongly suspect that the diluting
agent is always water. So, if the concentrate lasts for years,
don't see why the mixed would not as well. Also, if there
were a date issue, especially with only a few months, how
would they be able to sell the ready to use stuff? It would
go bad in the supply chain, stores, etc. Would need to have
a date on it and it doesnt.