Guides
Guides for getting the quantities right
The calculators give you a number. These guides explain where the number comes from, what to enter, and what to do with the answer once you have it.
Each one is written around a real decision: how deep, how far apart, bags or bulk, how much extra. They are arranged by the kind of question you are trying to answer.
Measuring
Getting a trustworthy number off the ground and into a calculator.
Cubic Yards, Cubic Feet and Liters: Garden Volume Without the Headache
Landscape materials are sold in cubic yards, bags are labeled in cubic feet or liters, and your bed is measured in feet and inches. Here is how the units fit together.
How to Measure an Irregular Garden Bed
Almost no garden bed is a tidy rectangle. Here are four ways to get a trustworthy area out of a curved, kidney-shaped or awkward bed, using a tape measure and some string.
Reading a Tape Measure and Converting Inches to Decimal Feet
Calculators want 12.5. Your tape says 12 feet 6 inches. Here is how to read the tape accurately and get from one to the other without mistakes.
Buying
How materials are sold, what to allow for, and how to get them home.
Bagged vs Bulk Mulch, Soil and Gravel: Finding the Break-Even Point
Bulk is cheaper per yard and bags have no delivery fee. Somewhere between the two is a break-even quantity, and you can work it out in one line.
How Much Does a Yard Weigh? Hauling Mulch, Soil and Gravel Safely
A pickup bed holds two cubic yards of anything. It can carry two cubic yards of almost nothing. Here is how to tell what your vehicle can really haul.
Ordering Garden Materials: Overage, Delivery Minimums and Returns
Knowing the quantity is half the job. The other half is knowing how suppliers sell it, what to ask before you pay, and what to do when the truck arrives.
Waste Factors Explained: Why 10% Is Often Wrong
"Add ten percent" is the most repeated advice in home improvement. It is right about a third of the time. Here is how to pick an allowance that fits the material and the shape of the job.
Soil & beds
Mulch, soil mixes and planting, with the quantities worked through.
From Tape Measure to Shopping List: Building and Filling a 4 × 8 Raised Bed
One raised bed, start to finish. The lumber, the cuts, the real inside dimensions, the soil, and the list to take to the store.
How Deep Should Mulch Be?
Two to four inches is the short answer. The useful answer depends on what the mulch is made of, what it is going around, and how much is already there.
Raised Bed Soil Mix: Ratios, Settling and What to Order
A raised bed is only as good as what you fill it with. Here is how the common recipes compare, what each ingredient is for, and how to order the right amount of each.
Square vs Triangular Plant Spacing: How Many More Plants Fit
Stagger the rows and the same bed holds about 15% more plants at the same spacing. Here is where that number comes from, when it is worth it, and how to mark it out on the ground.
Lawn
Starting a lawn and feeding it at the right rate.
How to Read a Fertilizer Label and Work Out How Much to Spread
Three numbers, a coverage claim and a spreader setting. Once you can read them, you can make any bag of fertilizer deliver exactly what your lawn needs and no more.
Sod vs Seed: Quantities, Cost and Timing Compared
Both make a lawn. One takes a weekend and a large check, and the other takes a season and some patience. Here is how to choose, and how much of each to order.
Hardscape
Bases, walls and concrete: the parts of the job that end up buried.
Bagged Concrete vs Ready-Mix: The Break-Even Point
Below about a cubic yard, bags usually win. Above two, the truck nearly always does. In between, it comes down to a short-load fee and how you feel about lifting two tons.
Paver Base Depth: How Much Gravel and Sand Goes Under a Patio
A paver patio lasts as long as its base. Here is how deep each layer should be, why, and how to turn those depths into tons of gravel and a pile of soil to get rid of.
Planning a Small Retaining Wall: Base, Batter and Drainage
A low block wall is one of the most satisfying garden projects, and one of the easiest to get wrong. The parts that matter are the ones you bury.
Structures
Posts, boards and spacing for fences and decks.
Deck Board Gaps and Joist Spacing: The Numbers Behind a Solid Deck
Two small measurements, the gap between boards and the spacing between joists, decide how a deck feels underfoot and how much material goes into it.
Fence Post Spacing and Depth: Planning the Layout Before You Buy
The posts decide everything else about a fence. Work out how many, how far apart and how deep before you buy a single board.