Drip Irrigation Run Time Calculator
Drip zones are scheduled per plant, not per square foot. Enter the water each plant should get per week and your emitters' output to get the run time per watering session.
Inputs
Result
Planning estimate - not a substitute for a pressure-tested engineering design.
Formula
Minutes per week = gallons per plant per week ÷ (emitters per plant × emitter GPH) × 60. Per session = weekly minutes ÷ watering days.
Example
5 gal/week per plant, two 1 GPH emitters, 2 watering days: 5 ÷ 2 × 60 = 150 min/week → 75 minutes per session.
Assumptions
- Emitter flow is at operating pressure (pressure-compensating emitters hold flow steady across a long line).
- Plant water targets are seasonal references, adjusted for local ET and soil.
- Sandy soils need shorter, more frequent sessions than clay.
Limitations
This tool is a planning aid for DIY design and pre-design work. It does not replace an on-site pressure and flow test, a catch-cup uniformity test, or local code and backflow requirements. For steep slopes, long pipe runs, large elevation changes or commercial-scale systems, have a qualified irrigation designer verify the plan before installation.
What This Means
Drip runs far longer than sprinklers - hours, not minutes - because it applies water slowly right at the root zone with 90%+ efficiency. Deep, infrequent watering encourages deeper roots.
Next Step
Plan the whole drip system with the Drip Irrigation Calculator, and budget weekly volume with the Water Budget Calculator.
Related Tools
Sources
Frequently Asked Questions
Why does drip run so much longer than sprinklers?
Emitters deliver a trickle (0.5-2 GPH vs 2 GPM for a spray head). The slow rate lets water spread through the soil instead of running off.
How many emitters does a plant need?
Enough to wet the whole root zone - usually 1 for small plants, 2-4 for shrubs and trees, spaced around the canopy edge.