Guide

How many spray tanks do I need?

The total of liquid, the full tanks, and the last tank, where most mistakes happen.

The calculation

Spray liquid = volume per acre × acres.
Tanks = liquid ÷ tank capacity, rounded up.
Product per full tank = dose per acre × acres one tank covers.
The last tank gets product only for the acres it covers.

Example

40 acres at 15 gal per acre: 600 gal. With a 500 gal tank: 2 tanks, one full and one of 100 gal. At 16 fl oz per acre, a full tank covers 33.3 acres and takes 533 fl oz; the last tank, 6.7 acres, takes 107 fl oz.

With Seed Calc

The Spraying tab gives the tanks, the product per full tank and in the last tank. See Spray tank calculator. Always follow the product label.

Other guides

NPK to urea, DAP, MOP

A soil test gives pounds of N, P and K. The dealer sells bags of products. Here is the bridge.

Seed rate per acre

Plants per acre from the spacing, seeds from the germination, pounds from the grain weight.

Calibrate a sprayer

A jug, a stopwatch and a measured pass give the gallons per acre your sprayer really applies.

Measure field area

Every quantity follows from the area. Here are the ways to get it, and how far to trust each.

Know what to buy before the season

Measure the field, enter your doses, send the list. No subscription.