Boom Sprayer Nozzle & The Flow Each Nozzle Needs

Required nozzle output in litres per minute = (target volume L/ha × forward speed km/h × nozzle spacing cm) ÷ 60000. The constant 60000 converts the mix of units (litres, km/h, cm, hectares) into a clean per-minute flow. The calculator does this for you and also shows the result in US gallons per minute so you can match a nozzle catalogue in either unit.

A boom sprayer applies the target spray volume per hectare by having every nozzle deliver a set flow at the chosen speed and spacing. If the flow is too high you over-apply and waste chemical; too low and you under-dose, risking poor control or resistance. Calculating the required flow lets you choose a nozzle and pressure that hit the target accurately and evenly across the boom.

Three things: the target spray volume per hectare (L/ha) from the product label or your agronomy plan, your forward speed in km/h, and the nozzle spacing along the boom in cm (commonly 50 cm). The calculator combines them into the required output per nozzle, plus the resulting spray volume per hectare and the speed, so you can confirm the setup.

Mark a measured distance in the field, drive it in the working gear and throttle you'll spray at — with a part-full tank for realistic weight — and time it. Speed (km/h) = distance (m) ÷ time (s) × 3.6. Use this real measured speed, not the speedometer, because tyre slip and terrain change ground speed and therefore the flow each nozzle needs.

Once you know the required flow per nozzle, pick a nozzle whose chart delivers that flow within its recommended pressure band — typically 1.5–4 bar for flat-fan nozzles. Staying in band keeps droplet size and pattern correct: too low and the fan collapses, too high and you make fine, drift-prone droplets. Adjust pressure only within the nozzle's range to fine-tune output.

Nozzle spacing is the distance between nozzles along the boom, usually 50 cm. It sets how much ground each nozzle covers, which directly affects the flow each must deliver for a given per-hectare volume. Wider spacing means each nozzle covers more ground and needs more flow; the calculator accounts for your actual spacing so the per-nozzle output is right.

Yes — this calculator gives you the target flow to select nozzles and a starting pressure, but always confirm with a real calibration: catch the output from several nozzles for a timed minute and check they match the target and each other. Worn nozzles over-deliver and uneven nozzles cause streaking, so physical checks remain essential. Use the Sprayer Calibration tool for the full procedure.

Yes — enter any target spray volume per hectare and the calculator returns the required nozzle flow for that rate, whether you're applying a low-volume herbicide or a high-volume fungicide. Just match the volume, speed and spacing to your job, and reselect nozzles when you change to a very different application rate or crop canopy.

The formula is exact for the inputs you give, but real application depends on accurate speed measurement, correct pressure, and nozzle condition and wear. Treat the output as the precise target to select and set nozzles, then verify by catching real output and checking coverage — good spraying combines the right calculation with a physical calibration.