Micro Sprinkler Coverage Calculator

Design efficient micro sprinkler layouts for healthy plants. Check overlap, spacing, and flow in minutes. Download reports and share them with your crew easily.

Calculator

Choose how you provide the plot size.
Use the radius at operating pressure.
Smaller arcs wet a smaller footprint.
Triangular can improve uniformity.
Distance between heads along a row.
Distance between rows of heads.
Typical range is 5–20%.
Used for application rate estimation.
Reset

Example Data Table

Plot (m²) Radius (m) Arc (deg) Layout X × Y (m) Sprinklers Application (mm/h) Status
2003.0360Square3 × 3236.90Good
1202.5180Square2.5 × 2.52010.00Borderline
3003.5360Triangular3.5 × 3.0335.50Good
Examples assume 60 L/h per sprinkler for application estimates.

Formula Used

  • Wetted area per sprinkler: Aw = (Arc/360) × π × r²
  • Area served per sprinkler (square grid): As = Sx × Sy
  • Area served per sprinkler (triangular): As = (√3/2) × Sx × Sy
  • Coverage ratio: CR = Aw / As
  • Target ratio with overlap: TR = 1 + (Overlap%/100)
  • Sprinklers needed: N = ceil(Plot Area / As)
  • Total flow: Qtotal = N × Qspr (L/h)
  • Application rate: mm/h = Qtotal / Plot Area (because 1 L/m² = 1 mm)
Guidance values are computed from As ≤ Aw/TR to suggest a maximum spacing in one direction given the other.

How to Use This Calculator

  1. Select how you will enter plot size.
  2. Enter plot dimensions or total area.
  3. Enter wetting radius at your operating pressure.
  4. Choose arc and layout pattern for your field.
  5. Enter spacing along rows and between rows.
  6. Set an overlap target for desired uniformity.
  7. Add flow per sprinkler to estimate application rate.
  8. Press Calculate and review the status message.
  9. Download CSV or PDF for records and sharing.

Footprint-Based Coverage Planning

Coverage mapping helps match emitter reach to plant geometry and soil intake. Micro sprinklers create a wetted disc, so spacing must keep adjacent discs overlapping enough to avoid dry stripes while still limiting wasted spray beyond root zones. When you enter radius and arc, the calculator converts that footprint into an effective area that can be compared with your proposed grid.

Spacing, Pressure, and Pattern Choice

Spacing interacts with pressure and nozzle choice. A small pressure drop can shrink radius and reduce uniformity, especially on long laterals or sloped beds. Use measured operating pressure at the head, then confirm radius using a catch‑can check. If your layout is triangular, the staggered rows reduce gaps, letting you cover the same plot with fewer heads at similar uniformity.

Wind, Height, and Site Obstacles

Wind and canopy height also influence distribution. Mounting higher increases diameter but can raise drift; mounting lower improves targeting under foliage. In greenhouses, low wind allows larger spacing, while open fields often need extra overlap. Consider obstacles like trellises and raised beds that block spray, and position heads to avoid shadows. Record adjustments so future expansions keep the same hydraulic balance.

Arc Management for Boundaries

Arc selection is practical for edges, pathways, and tree basins. Half and quarter patterns prevent overspray onto trunks, mulch rings, or hardscape. The calculator treats arc as a fraction of a circle, which quickly shows how partial patterns lower wetted area and may require tighter spacing or additional heads near boundaries.

Application Rate and Field Optimization

Flow inputs turn coverage into application rate. By multiplying heads by flow, the tool estimates millimeters per hour over the plot. Compare that rate to soil infiltration to reduce runoff on clay and prevent water stress on sandy soils. Use shorter cycles for slow soils and longer soaks for deep rooting crops.

Use the status message to iterate. If the ratio is risky, reduce spacing, raise radius with correct nozzles, or split the zone for better pressure control. After installation, keep filters clean, flush lines, and recheck uniformity each season to protect yield and plant health.

FAQs

1) How do I measure wetting radius accurately?

Run the system at normal pressure, then place small cups along a line from the head. The farthest point receiving consistent water defines radius. Repeat in two directions and use the average for planning.

2) What overlap target should I use for vegetables?

For most garden beds, 10–20% overlap improves uniformity and reduces dry strips. In windy areas or coarse soils, choose the higher end. In sheltered zones, you can often use lower overlap.

3) When is a triangular layout better than a square grid?

Triangular spacing staggers rows, reducing gaps between wetted circles. It can improve uniformity without tightening spacing as much. Use it where plants are evenly distributed and head placement flexibility is available.

4) Why does a partial arc reduce coverage so much?

Arc is a direct fraction of a full circle. A 180° head wets about half the circular area at the same radius, so the served area must shrink or more heads are needed near edges and corners.

5) What does the application rate in mm/h mean?

It is the average depth applied over the plot each hour. Compare it with soil infiltration and desired irrigation depth. A lower rate often needs longer runtime, while a higher rate may require shorter cycles.

6) My status shows Risk—what should I change first?

Start by reducing spacing in the direction with the largest gap. If pressure is low, improve hydraulics or use a nozzle with a larger radius. For edge zones, add partial‑arc heads rather than pushing spacing too far.

Tip: Verify radius and flow using the same pressure and filtration.

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Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.