Drip Irrigation Run-Time
Drip is the most efficient way to water, but only if you run it long enough. Enter your bed and emitters and get how many minutes, and how many days a week, to deliver the inch of water a garden wants, scaled to how hot your summers run.
Emitter flow rate
Set your place to scale for summer heat.
The math, simply
A gallon of water is two hundred thirty-one cubic inches, so the depth a drip line lays down per hour is the total flow of all its emitters times 231, divided by the bed area in square inches. Most gardens want about an inch of water a week, more in a heat wave and less in cool, wet stretches, split across two or three waterings so the soil wets deep without running off. Drip puts water at the roots with little lost to evaporation, so it does that on roughly a third the water of a sprinkler.
Formula from New Mexico State and Arizona Extension. A planning estimate; check soil moisture and adjust. Local rules may require backflow prevention.