A minute is not a volume
Ten minutes through eight one-gallon-per-hour emitters delivers a different volume than ten minutes through dripline with emitters every six inches. Count active emitters, verify their nominal rate, and catch-test a representative sample because pressure and clogging change actual output.
Water depth connects volume to bed area
One inch of water over one square foot is about 0.623 gallons. The calculator turns your chosen target depth into volume, divides by total measured flow, and splits the result across weekly sessions. The target itself must still respond to soil, crop stage, mulch, rain, heat, and local restrictions.
Check the root zone, not just the surface
After a trial run, wait for water to move through the soil and check moisture at useful root depth. A wet surface can hide a dry lower profile, while heavy soil may stay saturated long after the top looks ready for more.
- Inspect the far end of each line for pressure differences.
- Pause or reduce scheduled irrigation after meaningful rain.
- Repair leaks and clogged emitters before increasing runtime.
- Recheck as plant canopy and weather change through the season.
Sources & further reading
- Drip irrigation for home gardensUniversity of California Agriculture and Natural Resources
- Emitter evaluationsUniversity of California Agriculture and Natural Resources
- The do-it-yourself guide to backyard drip irrigationUtah State University Extension
- Watering the vegetable gardenUniversity of Minnesota Extension