Tree and Shrub Soil Drench Calculator

Standing in a yard with a list of trees and shrubs to drench, the number you need before you mix is product per plant times plant count. The label gives a rate per inch of trunk diameter (trees) or per foot of height (shrubs). Water volume varies by label: some state it per inch of DBH or per foot of height, others set a minimum per 1,000 square feet. Multiply, sum, and compare the total against the annual per-acre maximum before the season gets away from you. That is all this calculator does: the arithmetic the label assumes you will do by hand.

Add each tree or shrub to the plant list with its trunk diameter at breast height (DBH) or its height, a quantity, and an optional name so the printout reads like a job sheet. Enter the label rates for product and water, and the tool returns product per plant, water per plant, and running totals for both. Flip the unit toggles for metric entry (cm for diameter, liters for water, mL for product) and the results display in the selected units.

The annual-maximum check is the guard the label expects you to run yourself. Enter the label’s annual per-acre maximum and the treated area, and the calculator pro-rates the cap to your actual square footage: max for area = max per acre x (treated sq ft / 43,560). If the running total exceeds that figure, the tool flags it before you pour anything.

Every rate field starts blank. No default product rate is printed because the label is the only authority on what rate to use, and the label changes by product, pest, and site. The EPA Pesticide Product and Label System (PPLS) is where the binding document lives; this tool does the math once you have it.

The area-based spray coverage calculator at spray coverage calculator handles per-1,000-sq-ft and per-acre dosing for lawns and perimeter bands. For boom operators selecting the right tip, the sprayer nozzle size calculator derives GPM per nozzle from GPA, ground speed and spacing using the 5940 constant. This page is distinct: it doses per plant, by diameter or height, for soil drenches applied to individual trees and shrubs. For tank mixing with herbicides, see the herbicide tank mix calculator. To price the treatment program that wraps around these applications, see the lawn treatment program pricing calculator.