Many gardeners spent their middle-school days questioning the usefulness of math.

They wondered, “When will I ever have to calculate the area of a circle in real life?” or “Why is knowing how to figure the volume of a box useful?”

Why? Because gardening is full of everyday math calculations: figuring fertilizer rates, mixing chemicals using ratios, determining volumes of planters to be filled with potting soil, measuring square feet to cover with mulch.

So, for gardeners with limited math skills, here are a few useful calculations to help you become a more calculating gardener:

Linear measure

12 inches = 1 foot

3 feet = 1 yard

1 mile = 1,760 yards = 5,280 feet

Circumference of a circle = 2 x 3.14 x radius

(With 3.14 being pi and the radius is measured from the center of the circle to the edge, or measuring across the circle and dividing by 2.)

This calculation is useful when buying edging to put around trees and flowerbeds, when building brick patios or figuring how much wire is needed to install accent lighting.

Square measure or area

1 square foot = 144 square inches

1 square yard = 9 square feet

1 acre = 43,560 square feet

Area of a square or rectangle = length x width

This calculation is useful in determining the area of a lawn for fertilizing, how many bricks to buy for a brick patio, how many plants are needed to fill a garden or how much mulch to purchase to cover a flower bed.

A three-cubic-foot bag of mulch will cover: 36 square feet, 1 inch deep; 18 square feet, 2 inches deep; 12 square feet, 3 inches deep; 9 square feet, 4 inches deep.

A cubic yard of mulch will cover: 162 square feet, 2 inches deep; 108 square feet, 3 inches deep; and 81 square feet, 4 inches deep.

Area of a circle = 3.14 x (radius x radius)

(square the radius and multiply by 3.14 or pi)

This calculation is effective when figuring the areas of the items above, but when they are round.

Cubic measure or volume

1 cubic foot = 1,728 cubic inches and holds 7.5 gallons

1 cubic yard = 27 cubic feet

1 gallon = 231 cubic inches

Volume of a cylinder = (area of circle base) x (height of cylinder)

Volume of a box = length x width x height

These calculations are useful when figuring how much potting soil to buy to fill circular or square planters, or knowing how much chemical to use when treating an ornamental fish pond.

Gardening is more than just digging in the dirt. Sometimes knowing a few simple math tricks can make the job easier and more successful.