Drip Irrigation Calculator
Design your drip irrigation system.
Enter number of plants, emitter flow rate, and water pressure to calculate system requirements and run time.
Irrigation System Design
Drip irrigation design ensures each plant gets adequate water without exceeding your water supply capacity.
Key formulas:
Total Flow Rate (GPH) = Number of Emitters x Emitter Flow Rate (GPH)
Run Time (hours) = Water Needed per Plant (gal) / Emitter Flow Rate (GPH)
Total Water per Session (gal) = Total Flow Rate x Run Time
Common emitter flow rates:
- 0.5 GPH (2 L/hr): Small plants, herbs, flowers
- 1.0 GPH (4 L/hr): Vegetables, small shrubs
- 2.0 GPH (8 L/hr): Large shrubs, small trees
- 4.0 GPH (15 L/hr): Trees, large plants
Water needs by plant type (per session):
- Herbs/flowers: 0.5–1 gallon (2–4 L)
- Vegetables: 1–2 gallons (4–8 L)
- Shrubs: 2–5 gallons (8–19 L)
- Trees: 5–15 gallons (19–57 L)
Pressure considerations:
- Most drip systems work at 15–30 PSI (1–2 bar)
- Use a pressure regulator if supply exceeds 30 PSI
- Mainline tubing (1/2"): supports up to 200 GPH at 25 PSI
- Low pressure (< 15 PSI) reduces emitter output significantly
Tip: Install a filter to prevent emitter clogging. Flush lines monthly.