# A question about herbicide mix rates.



## Tim H (May 31, 2018)

So let's say I buy a 18% glyphosate Roundup that calls for 6 oz per gallon mixture rate. If I add 12 oz per gallon, do I now have a 36% glypho solution? The smaller glypho percentages are a lot cheaper than the higher concentrations for the most part. Just curious to see if I can save a few bucks and make a stronger solution.


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## gene_stl (Oct 29, 2017)

If it is 18% and calls for 6 oz per gallon (128 oz) they are calling for you to spray a 4.6875% x0.18 solution (6 divided by 128)X0.18= 0084375 or 0.84375% less than one percent final solution.

If you double that and make it up to a gallon of water (in both cases as opposed to adding it to an already full gallon)
your final percentage would be 9.3750 % x0.18 = 0.0168750 or 1.68750% final concentration.

Normally when you buy chemicals the more concentrated form is more economical to buy and use although it may cost more and frequently has you buying more than you will use in a year or so. Mostly they keep well if you put them in the basement and keep the lids closed tight.

Many people use 3 oz of 41% glyphosate per gallon which equals a final concentration of 0.9609375 % or just under 1% active ingredient and that is plenty hot.


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