Determining Pesticide to Gallon of Water Rate
One of the most commonly asked questions is how much product do I add to one gallon of water.
There are lots of guides out there that can be overwhelming. The truth is there are a lot of variables that go in to spraying. Pressure, nozzle type, width of spray pattern, volume of spray coming out of spray gun, turf type, temperature, health of turf sprayed, fertilizer used, type of pesticide (herbicide / insecticide / fungicide ), your personal average walking speed are all important. Knowing these variables and calibrating your sprayer can save a lot of time and possible accidental injury to off target species when spraying.
But all you want to know is the product to water fl. oz./gal. ratio!
Well without knowing your particular sprayers calibration or any of these other variables we will have to make some assumptions.
1 Acre = 43560 Square Feet
Rounded up to the nearest thousandth = 44000 Square Feet
Some people use more some use less water per acre.
So let’s assume…
Sprayers typically range from 0.5 - 2 Gallons of water per 1000 square feet.
At that range you would need 22 – 88 gallons of water per acre.
Take the number of fluid ounces called for per acre in the label.
Divide that number by the amount of gallons of water you use per acre.
For Example:
0.5 Gallon per 1000 square feet = 0.5 x 44 = 22 gallons of water per acre
1 Gallon per 1000 square feet = 1 x 44 = 44 gallons of water per acre
2 Gallons per 1000 square feet = 2 x 44 = 88 gallons of water per acre
For Example:
The label calls for 1 quart per acre (32 fl. oz.)
Lets use 1 Gallon of water per 1000 sq. ft. (44000 sq. ft. in acre rounded up)
32 / 44 = 0.73
You would use 0.73 of a fluid ounce per gallon of water.
The amount of fluid ounces called for on the label are divided by 44.
Below are examples of use rates at one gallon per 1000 square feet.
1/44 = .023 fl. oz. per gallon of water
2/44 = .045 fl. oz. per gallon of water
3/44 = .069 fl. oz. per gallon of water
4/44 = .091 fl. oz. per gallon of water
5/44 = .11 fl. oz. per gallon of water
6/44 = .14 fl. oz. per gallon of water
7/44 = .16 fl. oz. per gallon of water
8/44 = .18 fl. oz. per gallon of water
9/44 = .2 fl. oz. per gallon of water
10/44 = .23 fl. oz. per gallon of water
11/44 = .25 fl. oz. per gallon of water
12/44 = .27 fl. oz. per gallon of water
13/44 = .3 fl. oz. per gallon of water
14/44 = .32 fl. oz. per gallon of water
15/44 = .34 fl. oz. per gallon of water
16/44 = .36 fl. oz. per gallon of water
32/44 = .73 fl. oz. per gallon of water
64/44 = 1.45 fl. oz. per gallon of water
128/44 = 2.91 fl. oz. per gallon of water
Conversions:
Gallon = 128 Fl. Oz.
Half Gallon = 64 Fl. Oz.
Quart = 32 Fl. Oz.
Pint = 16 Fl. Oz.
Tablespoon = 0.5 Fl. Oz.