How long to spray 100 acres depends on sprayer type and refill stops. With the example tank sizes, application rates and refill times in this guide, total clock time runs from about 0.91 hours with a 120 ft self propelled sprayer to about 16.35 hours with a 15 ft ATV sprayer. Field work alone runs from 0.58 to 13.10 hours.
The Formula Behind the Time
Acres per hour is boom width in feet times speed in miles per hour times efficiency, divided by 8.25. The constant 8.25 equals 43560 divided by 5280. Efficiency is written as a decimal, so 85 percent becomes 0.85. Speed is the average speed you can hold safely while the spray pattern stays even. Speed changes the application rate unless the sprayer has rate control, so always calibrate and follow the product label for rate, nozzle and weather conditions.
Time for a field is field acres divided by acres per hour, using the unrounded rate and rounding only the final time. A 6 foot tool at 4.5 miles per hour and 75 percent efficiency gives 2.45 acres per hour, and a 20 acre field at 2.45 acres per hour takes about 8.2 hours, never 8.1 hours. Run your own numbers through the Spraying Acres Per Hour Calculator. The how to calculate acres per hour guide gives the formula in full.
How Long to Spray 100 Acres by Sprayer Type
The table below gives the verified spraying rate for each sprayer type, and the field work time for 100 acres at that rate. Field work time here means spraying time only. It does not include refilling the tank, mixing, travel, turns, or breaks. Those stops are added later, so read this table as the starting point, not the day plan.
| Sprayer | Boom width | Speed | Efficiency | Acres per hour | Field work for 100 acres |
|---|---|---|---|---|---|
| ATV UTV sprayer | 15 ft | 6 mph | 70 percent | 7.64 | 13.10 hours |
| 3 point pull type | 40 ft | 8 mph | 75 percent | 29.09 | 3.44 hours |
| Pull type | 60 ft | 10 mph | 80 percent | 58.18 | 1.72 hours |
| Self propelled | 90 ft | 12 mph | 85 percent | 111.27 | 0.90 hours |
| Self propelled | 120 ft | 14 mph | 85 percent | 173.09 | 0.58 hours |
The ATV sprayer takes 13.10 hours, the 3 point sprayer takes 3.44 hours, the 60 foot pull type sprayer takes 1.72 hours, the 90 foot self propelled sprayer takes 0.90 hours, and the 120 foot self propelled sprayer takes 0.58 hours, or about 35 minutes. The gap is wide because width, speed and efficiency all rise together in the table.
The Before Refill Baseline From Blog 13
Blog 13 on this site gives time for 100 acres by boom width at a fixed 10 miles per hour and 80 percent efficiency, with field work only and no refill time. Its figures are the before refill baseline for this guide.
| Boom width | Field work for 100 acres at 10 mph and 80 percent |
|---|---|
| 20 ft | 5.16 hours |
| 30 ft | 3.44 hours |
| 40 ft | 2.58 hours |
| 60 ft | 1.72 hours |
| 90 ft | 1.15 hours |
| 120 ft | 0.86 hours |
At the Blog 13 settings, 100 acres takes 5.16 hours at 20 feet, 3.44 hours at 30 feet, 2.58 hours at 40 feet, 1.72 hours at 60 feet, 1.15 hours at 90 feet and 0.86 hours at 120 feet. Those times are not total clock times, because they leave out every refill stop. In this guide, a 40 foot sprayer takes 3.44 hours, not 2.58 hours, a 90 foot sprayer takes 0.90 hours, not 1.15 hours, and a 120 foot sprayer takes 0.58 hours, not 0.86 hours, because each runs at its own speed and efficiency.
Why Refill Time Changes the Answer
A sprayer sprays until the tank is empty, then it stops to refill and mix, then it sprays again. The refill cycle method from the live rewrite works out that stop in three steps. First, acres per tank equals tank gallons divided by GPA. Second, spraying time per tank equals acres per tank divided by acres per hour, using the unrounded rate. Third, a full cycle equals spraying time per tank plus refill minutes, and real output equals acres per tank divided by the cycle time in hours.
Two verified examples show the method. A 90 foot sprayer at 12 miles per hour and 85 percent covers 111.27 acres per hour while spraying. With a 1000 gallon tank at 15 GPA, it covers 66.7 acres per tank, spraying time per tank is about 36 minutes, and a 20 minute refill gives a 56 minute cycle and real output of 71.5 acres per hour. A 60 foot sprayer at 10 miles per hour and 80 percent covers 58.18 acres per hour while spraying. With a 1200 gallon tank at 10 GPA, it covers 120 acres per tank, spraying time per tank is about 124 minutes, and a 15 minute refill gives a 139 minute cycle and real output of 51.9 acres per hour. Those figures are per full cycle. For a 100 acre block, the exact total is different, because the last tank is only a part tank, and no refill is needed after the job is finished.
Tank size and GPA decide how often you stop, and refill minutes decide how much each stop costs. Every total time in this guide states its GPA, tank size and refill minutes as labeled example inputs. There is no standard tank size, GPA or refill time in this guide.
Total Clock Time for 100 Acres Including Refills
The table below gives total clock time for 100 acres for each sprayer type, using the labeled example inputs in the same row. Total clock time equals field work time plus refill time for the refill stops actually needed. Tank loads are rounded up to whole loads for planning, and refill stops equal tank loads minus one, because the job starts with a full tank and no refill is needed after the last pass. Total mix equals 100 acres times GPA.
| Sprayer | Example inputs | Acres per tank | Tank loads | Refill stops | Total mix | Total clock time |
|---|---|---|---|---|---|---|
| ATV UTV sprayer | 25 gal tank, 10 GPA, 5 minute refill | 2.50 | 40 | 39 | 1000 gal | 16.35 hours |
| 3 point pull type | 300 gal tank, 15 GPA, 15 minute refill | 20.00 | 5 | 4 | 1500 gal | 4.44 hours |
| Pull type | 300 gal tank, 15 GPA, 15 minute refill | 20.00 | 5 | 4 | 1500 gal | 2.72 hours |
| Self propelled | 1000 gal tank, 15 GPA, 20 minute refill | 66.67 | 2 | 1 | 1500 gal | 1.23 hours |
| Self propelled | 1200 gal tank, 15 GPA, 20 minute refill | 80.00 | 2 | 1 | 1500 gal | 0.91 hours |
An ATV UTV sprayer, with a 25 gallon tank at 10 GPA and a 5 minute refill as the labeled example, covers 2.50 acres per tank, needs 40 loads, and stops 39 times. Field work is 13.10 hours, refill time is 3.25 hours, and total clock time is 16.35 hours, more than two 8 hour working days. A 3 point pull type sprayer, with a 300 gallon tank at 15 GPA and a 15 minute refill, covers 20.00 acres per tank, needs 5 loads, and stops 4 times. Field work is 3.44 hours, refill time is 1.00 hour, and total clock time is 4.44 hours. A 60 foot pull type sprayer, with the same example inputs, also needs 5 loads and stops 4 times. Field work is 1.72 hours, refill time is 1.00 hour, and total clock time is 2.72 hours.
A 90 foot self propelled sprayer, with a 1000 gallon tank at 15 GPA and a 20 minute refill, covers 66.67 acres per tank, needs 2 loads, and stops once. Field work is 0.90 hours, refill time is 0.33 hours, and total clock time is 1.23 hours, or about 74 minutes. The real output per full cycle is 71.5 acres per hour, which gives 1.40 hours if you divide 100 by that rate. The exact total is lower, because the second tank is only a part tank of 33.33 acres. A 120 foot self propelled sprayer, with a 1200 gallon tank at 15 GPA and a 20 minute refill, covers 80.00 acres per tank, needs 2 loads, and stops once. Field work is 0.58 hours, refill time is 0.33 hours, and total clock time is 0.91 hours, or about 55 minutes. Tank size can remove a refill entirely. The verified large tank example for the 60 foot sprayer uses a 1200 gallon tank at 10 GPA. It covers 120 acres per tank, so 100 acres needs only 1 load and 0 refill stops, and total clock time is 1.72 hours.
What Changes Your Time on a Real Field
Field efficiency changes the time before refills are even counted. The bands used on this site are 55 to 65 percent for small or irregular fields, 70 to 75 percent for average fields, 80 to 85 percent for large rectangular fields, and 85 to 90 percent for ideal fields with GPS guidance. A small field with short passes and many turns sits at the low end. A large rectangular field with long passes sits at the high end. Use the guide on understanding field efficiency to pick an efficiency that matches your field shape.
A lower efficiency moves the time by a clear amount. A 90 foot sprayer at 12 miles per hour and 70 percent efficiency covers 91.64 acres per hour, not 111.27, so field work for 100 acres rises from 0.90 hours to 1.09 hours, before refills. A 60 foot sprayer at 10 miles per hour and 70 percent efficiency covers 50.91 acres per hour, not 58.18, so field work rises from 1.72 hours to 1.96 hours, before refills. Weather, travel, setup and breaks sit outside the times in this guide. The guide on sprayer acres per hour and refill time gives the refill method in full.
Frequently Asked Questions
Q: How long does it take to spray 100 acres with a self propelled sprayer?
A: A 90 foot sprayer takes 1.23 hours in total, with a 1000 gallon tank at 15 GPA and one 20 minute refill. A 120 foot sprayer takes 0.91 hours in total, with a 1200 gallon tank at 15 GPA and one 20 minute refill.
Q: How long does it take to spray 100 acres with a pull type sprayer?
A: With a 300 gallon tank at 15 GPA and a 15 minute refill, a 60 foot sprayer takes 2.72 hours in total, with 4 refill stops. With a 1200 gallon tank at 10 GPA, the same sprayer takes 1.72 hours, with 1 load and no refill stop.
Q: How long does it take to spray 100 acres with an ATV sprayer?
A: With a 25 gallon tank at 10 GPA and a 5 minute refill, a 15 foot ATV sprayer takes 16.35 hours in total, with 39 refill stops. That is more than two 8 hour working days.
Q: How many tank loads does it take to spray 100 acres?
A: With the example inputs in this guide, an ATV sprayer needs 40 loads, a 3 point sprayer needs 5 loads, a 60 foot sprayer needs 5 loads, a 90 foot sprayer needs 2 loads, and a 120 foot sprayer needs 2 loads.
Q: Does the Blog 13 time for 100 acres include refill time?
A: No. Blog 13 gives field work time only, at a fixed 10 miles per hour and 80 percent efficiency, all before refills.
Q: How much spray mix does 100 acres need?
A: Total mix equals 100 acres times GPA. At 15 GPA, 100 acres needs 1500 gallons. At 10 GPA, 100 acres needs 1000 gallons.
Plan the Day From Total Clock Time, Not Field Work Time
How long to spray 100 acres is a total clock time question, not a field work question. Field work runs from 0.58 to 13.10 hours by sprayer type, and refills add from 0 hours to 3.25 hours on top. With the example inputs in this guide, total clock time runs from 0.91 hours for a 120 foot self propelled sprayer to 16.35 hours for a 15 foot ATV sprayer. Work out your own numbers with the Spraying Acres Per Hour Calculator before the next job.
