Calculating fertilizer injector runtime?

Bluelude1

LawnSite Member
This is a fringe question if there ever was one ...If you were injecting fertilizer into an irrigation system and you knew the following

PPM of Nitrogen in fertilizer stock tank
Injection ratio (1:500 - 1:40)
Zone flow rate
Zone precipitation rate (matched)
But you didn't know the exact sqft being irrigated (I guess it could be roughly calculated from flow & precipitation rates) how would you go about determining zone runtime to put out 1lb N/1000sqft at an injection ratio of say 1:100 ?

RigglePLC

LawnSite Fanatic
Assume an area of 1000 sqft.
Apply a tenth of a foot. This is 100 cubic feet.
This equals 750 gallons.
Use the injection ratio of 1 to a 100.
You will inject 7.5 gallons.
You need .13 lbs N per gallon.
That is 130,000 ppm nitrogen.

On the other hand--do your own homework.

OP
B

Bluelude1

LawnSite Member
Assume an area of 1000 sqft.
Apply a tenth of a foot. This is 100 cubic feet.
This equals 750 gallons.
Use the injection ratio of 1 to a 100.
You will inject 7.5 gallons.
You need .13 lbs N per gallon.
That is 130,000 ppm nitrogen.

On the other hand--do your own homework.
Thanks for breaking it down. I haven't found an article yet that was as concise.