Roundup life

[Haneyman]

How long does Roundup stay good if mixed in a tank?
Would like to mix 20 gallons and use little at a time over 2-3 months
Thanks,Mike

 

[seville009]

I had some of the little gallon (I think) jugs with the sprayer on it for homeowner usage in my shed for two years. Eventually used it to kill the grass around my pool and it still worked fine.

 

[5030]

90 days is fine but be sure to agitate it to mix it up before using it.

 

[GeneV]

It may be less effective than when fresh, but I've used your old Roundup and even to 2 year old Roundup, it worked.

 

[GeneV]

Shake it up before using it.

 

[flyerdan]

I got a 2.5 gallon jug of knock-off Roundup from Home Depot when it was $40, so several years ago. I mixed a batch this spring and it did fine; it's kept in the shop, dark and above freezing.
No idea on mixed longevity, I have a 3 gallon sprayer and two batches will barely do what I need done.

 

[jyoutz]

How long does Roundup stay good if mixed in a tank?
Would like to mix 20 gallons and use little at a time over 2-3 months
Thanks,Mike

I always mix some early in the summer and use it all season. Seems to work fine.

 

[old and tired]

What are you mixing it in? If you are doing this in a sprayer with a PTO pump, the RoundUp mix is fine but it will corrode the pump (depending on the quality of the pump). I make sure to wash and clean and oil the pump after use.

 

[Haneyman]

We’re mixing in a plastic spot sprayer tank with a rural king diaphragm 12 volt pump

 

[5030]

We’re mixing in a plastic spot sprayer tank with a rural king diaphragm 12 volt pump

You are good. The diaphragm pump has synthetic rubber guts.

 

[bigtiller]

What am I doing wrong?
I have never had any leftover mix in the 1.5 gallon sprayer last more than 2 weeks without getting chunky and clogging the tip.

Does it simply need shaken up more?