Please confirm my math for a hose end sprayer


Old 06-22-18, 12:26 PM
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Please confirm my math for a hose end sprayer

I'm thinking of purchasing a couple pints of Eagle 20W fungicide. I have a Gilmour 362 hose end sprayer that I bought a while ago but have never used.

The Eagle label says to use 1.2 oz/1,000 sq ft, and then later says to use 1 gallon of water per 1000 sq ft

Is it correct to say that I should use 1.2 oz/gallon (or is there some other math that needs to be done)?

Assuming it's 1.2 oz/gallon (per 1k sq ft), and I have 20k sq ft, I'd need 20 x 1.2 oz = 24 oz of Eagle to cover all 20k sq ft, correct? The sprayer holds 16 ounces, so I'd probably break my yard into 3 sections and put in 8 ounces, 3 times.

Also, the settings on the sprayer are in tablespoons per gallon. Since 1.2 oz = 2.4 tablespoons, I'd either have to use setting 2 or 3 (or halfway if I can get that to work, which I'm not sure I can).

Finally, do I just spray at a modest pace, and hope/assume that 1 gallon of water (with 1.2 oz of Eagle) is covering 1000 sq ft? Would I just eyeball the bottle after walking what I'm pretty sure is 1000 sq ft and confirm that there's 1.2 ounces less in the container?

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Old 06-22-18, 01:55 PM
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Yeah, I find this to be as much of a crapshoot as you do. I sprayed some stuff last year and it didn't do the job I had hoped but I did manage to finish spraying pretty close to the point where I had covered the whole yard. Next time out I turned the sprayer concentration up another notch and spent more time spraying so I put considerably more of the herbicide in each area and that time it worked pretty well so the next time I will start with those settings.
In other words, I find there to be quite a bit of trial and error in this.
Old 06-22-18, 02:01 PM
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Thank you. I'll give it a try and see how it goes.
Old 06-22-18, 02:45 PM
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I really don't like to apply chemicals with a hose end sprayer. They aren't precision instruments so it's almost a guess as to how much product you are putting out.

I set my sprayer to a low setting. Then I go over the spray area quickly. Hitting everything but moving quickly to insure I don't run out of product. Then I keep making quick passes over the area until the product is done. This way each pass puts out a thin layer of product. If you miss a spot on one pass you'll likely hit it on the next. You do more walking but it helps insure an even application especially versus trying to do it all in one pass.
Old 06-26-18, 06:28 AM
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That's a great idea. I'll give that a try. Thank you.
Old 06-26-18, 10:52 AM
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I would time how many seconds it takes for your hose end sprayer to fill up a gallon bucket. Just to give you an idea of how fast you will need to move.
Old 06-27-18, 06:30 AM
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I like XSleeper's idea. If the square feet covered per gallon is too big a test area or the time to spray a gallon is long, divide the numerator and denominator (coverage per gallon) and time to spray a gallon by the same number that makes the test area or time to spray reasonable. Mark off the calculated test area, mix the calculated amount solution, start the timer and go. The variable is the speed at which you move. Good luck.

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