Drip Irrigation Calculator

Overview

Lays out parallel drip rows from bed width and plant spacing, then counts emitters, tubing, stakes, and connection components.

Assumptions

• Rows and emitters are rounded up from the entered spacing.
• Each emitter is listed as 1 GPH.

Worked example

A 20 × 4 ft bed at 18-in spacing has ceil(4 ÷ 1.5) = 3 rows and ceil(20 ÷ 1.5) = 14 emitters per row: 42 emitters.

Common mistakes

• Counting plants but not supply-line routing.
• Running drip without filtration or pressure regulation.

Limitations

It does not calculate pressure loss, zone capacity, or plant-specific water needs.

Safety and local requirements

Use a backflow device where required and check local watering rules before connecting to potable water.

Sources

• EPA WaterSense — irrigation efficiency background