as soon as I"m trying to figure out just how much come water things in my garden I"ll regularly see things like, "...they will need 1-2 customs of water every week."

From what ns understand, this is the very same as if there had been 1-2 inch of rain. My problem is that everything for drip watering systems it seems to be ~ to measure up in gallons or liters every hour.

How have the right to I go about converting inches to gallons?


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One us gallon is 231 cubic inches.

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One square yard is 1296 square inches.

So "1 customs of rain" is 1296/231 or around 5 and also a fifty percent US gallons or 21 liters the water per square yard.

The flow rate with your drip device obviously depends on the area it is watering and how countless hours that is on every day, however that provides you a starting point.

Note: 1 imperial (UK) gallon is 277 cubic inches which gives 4 and also three 4 minutes 1 UK gallons every square garden - however commercial UK irrigation systems will be specified in metric units so that is relatively irrelevant.


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edited Jul 22 "19 at 9:17
answered Jul 22 "19 in ~ 9:09
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alephzeroalephzero
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I simply went through the same thing myself when setup up my drip irrigation system. It"s actually pretty easy.

The formula is as follows:

Pr = 96.25 x full GPM of all emitters (gal/min) ------------------------------------------- complete area (ft²)Where Pr is the "precipitation" rate in inches/hour.

To make it more clear, I"ll take an instance from my own garden. I have actually 6 slicing tomato plants planted in about an 18" x 3" area. I have actually 2 sections of drip tubing that stretch ~ above either side of the tree which provide a total of 29 0.9 gal/hour (GPH) emitters within the area. I likewise have secondary single 1 GPH emitter for each plant.

So, to uncover the total GPM of every emitters (gal/min) I execute the following:

29 x 0.9 gal/hr = 26.1 gal/hr

6 x 1.0 gal/hr = 6 gal/hr

26.1 gal/hr + 6 gal/hr = 32.1 gal/hr

To acquire gal/min, divide by 60:

32.1 gal/hr / 60 = 0.535 gal/min

So, plug that right into the equation and also you get

Pr = 96.25 x 0.535 gal/min --------------------- 18 x 3So, Pr = 51.5 / 54 or .954 inches/hour

Let"s say I want to give them 2 customs of water every week. In ~ 0.954 in/hr, I"d must water a total of 2.097 hours, or 126 minutes per week.

I compared this calculated an approach to an actual physical test (held bath tub underneath 2 of the drip ice emitters because that 30 minutes), and also it"s pretty lot dead on.

See more: What Is 60 Divided By 8 ? With Remainder, As Decimal, Etc With Remainder, As Decimal, Etc

I very recommend setting this up together a spreadsheet through columns for width and also length, and then columns for the amounts of each rate emitter girlfriend have.