Landscaping: Calculators, Diagrams & Guides
6 calculators · 13 diagrams · 4 guides
Bulk landscape material is ordered in units nobody visualizes well: cubic yards of mulch, tons of gravel, and the perpetual question of whether bags or a bulk delivery is the better call. The three calculators in this hub settle it — area × depth converted to yards, yards converted to tons by material density, bag counts at every common bag size, and the bag-versus-bulk crossover point where a delivery starts beating the cart-load math.
The diagrams teach the details that keep material working instead of just sitting there: correct mulch depth by use (2 to 3 inches in beds — more suffocates roots), the donut-not-volcano rule at tree trunks, gravel compaction loss between loose and placed depth, and the density ladder that explains why a yard of river rock weighs nearly twice a yard of hardwood mulch.
Coverage rules follow supplier and extension-service conventions — a cubic yard covers about 108 square feet at 3 inches — and density figures come from published material weights, not guesses. The cubic-yards feeder calculator underneath the whole hub handles any area-times-depth conversion you throw at it, and every tool here is free with no signup — measure the beds, pick a depth, and order once.
Landscaping calculators
- Mulch CalculatorInstantly calculate mulch in cubic yards & bags for any bed size. Compares bulk vs bagged cost. Free, accurate landscaping calculator—no signup.
- Gravel CalculatorFree gravel calculator with material-specific densities, compaction factor & waste overage. Get cubic yards, tons & bag count in seconds.
- Landscape Material CalculatorCalculate cubic yards, tons & bags for gravel, crushed stone, sand, river rock, topsoil, and riprap. ASTM D448 / AASHTO M43 gradations. Free.
- Sod CalculatorFree sod calculator: square feet, slabs, rolls, and pallets for your lawn — with editable, region-aware pallet coverage plus topsoil and starter fertilizer.
- Topsoil CalculatorFree topsoil calculator with project depth presets for new lawns, garden beds & raised beds. Get cubic yards, tons, bags & a raised-bed blend split.
- Grass Seed CalculatorFree grass seed calculator with extension-cited rates by species for new lawns, overseeding & winter overseed. Get pounds to buy, bags, and starter fertilizer.
Guides & references
Landscaping · 13 diagrams
- Landscaping
How deep should gravel be? Compacted base depth by use — walk, driveway, street
Gravel depth is not one number — it climbs with the load. ICPI Tech Spec 2: 4–6″ of compacted aggregate base under walks, 6–8″ under driveways, 8–12″ under streets; decorative cover is 2–3″. Foundation drainage (IRC R405.1) uses ≥4″ of open-graded #57.
- Landscaping
Order loose, place compacted — the gravel compaction factor by material class
Gravel ships loose and densifies under the plate, so you order more than the finished bed holds. Dense-graded crusher run ×1.20 (15–25% settlement), open-graded #57/#67 ×1.10 (~8%), rounded decorative stone ×1.00 (does not compact). Loose order = compacted volume × the material multiplier.
- Landscaping
How deep should mulch be? Mulch depth by application — beds, trees, pathways
Mulch depth is not one number — it tracks the planting. Fine cover 1–2″, flower beds 2–3″, trees & shrubs 3–4″, wood-chip paths a full 4″. Stay in the 2–4″ band: under 2″ won’t suppress weeds or hold moisture, over 6″ suffocates roots. Measure what’s down and top up to depth.
- Landscaping
Mulch volcano vs mulch donut — how to mulch around a tree without rotting the trunk
Same volume, two shapes. The volcano piles mulch against the bark — trapped moisture rots the trunk, buries the root flare, and drives girdling roots. The donut lays an even 2–4″ layer pulled 3–6″ back from the trunk, keeping the root flare dry and tapering out to the drip line (ISA guidance).
- Landscaping
Landscape area take-off — rectangle, circle, triangle, and ring-bed formulas summed per section
A bed rarely is a clean rectangle. Add one section per shape and the calculator sums the areas: rectangle = L × W, circle = π(D/2)², triangle = ½ × B × H, and a ring around a tree = π(R² − r²) — remember to subtract the trunk gap. Total area × depth = the volume you order.
- Landscaping
Landscape material weight — one cubic yard is 0.65 tons of lava rock but 1.5 tons of riprap
Cubic yards and tons don’t line up the same way for every material — planning densities run from ~1,300 lb/yd³ (lava rock) to ~3,000 lb/yd³ (riprap). So one cubic yard is 0.65 tons of lava rock but 1.5 tons of riprap, and a ton of a light material covers far more ground. Compare prices per cubic yard (volume), not per ton.
- Landscaping
Bagged, bulk, or dump truck — order size decides, with a ~2 yd³ bulk break-even
The order size in cubic yards picks the format: under ~½ yd³, bagged (delivery minimums make bags practical); ½–2 yd³ is the crossover; past the ~2 yd³ break-even, bulk delivery on a single-axle dump (~5–8 yd³) wins; ≥ 6 yd³, a tandem dump (10–14 yd³) beats two loads. And a ½-ton pickup carries only ~1,500 lb — under one cubic yard for most materials.
- Landscaping
How deep should topsoil be? Topsoil depth by project — topdressing, lawn, garden bed, raised bed
Topsoil depth is never one number — it tracks the project. Topdressing ¼–½″ per pass, a new lawn (seed or sod) 4–6″, garden beds 6–8″, raised beds 8–12″ for leafy crops and 12–24″ for deep-rooted. The calculator picks depth from the project type before it computes volume.
- Landscaping
Grade-change fill — fill-dirt body with a 4–6″ screened-topsoil cap, sloped away from the foundation
Don’t build a grade change out of topsoil. Bulk it 60–70% with compactable fill dirt, then cap the top 4–6″ with screened topsoil for a root zone. Grade must still fall away from the foundation — IRC R401.3 wants a 6″ drop over the first 10 ft (≈½″/ft).
- Landscaping
How much grass seed per 1,000 sq ft? New-lawn seeding rate by species — bermuda, bluegrass, ryegrass, fescue, bahia
There is no single seeding rate — it tracks the species, and the spread is 4–5×. New-lawn rates run bermuda 1–2 lb, Kentucky bluegrass 2–3, perennial rye & fine fescue 4–5, bahia 5–10, and tall fescue 6–10 lb per 1,000 ft². The calculator reads the rate off the species you pick, and flags sod-only grasses (St. Augustine, zoysia) instead of guessing.
- Landscaping
New lawn vs. overseed vs. winter overseed — how the use case sets the grass-seed rate
The same grass takes a different rate depending on the job. A new lawn on bare ground uses the full rate (tall fescue 8 lb/1,000 ft²); overseeding a thin lawn is roughly half (4 lb) because turf is already there. Winter-overseeding dormant bermuda or zoysia swaps species entirely — cool-season perennial ryegrass (6–10 lb), not the warm grass’s own seed.
- Landscaping
Measuring an irregular lawn for sod — the offset method
For a curved lawn, run a centerline, measure widths across it at even intervals, and multiply the summed widths by the interval: (40+30+50) × 10 = 1,200 sq ft. Then subtract beds and driveways and add 5–10% waste.
- Landscaping
Sod anatomy and the brick-stagger laying pattern
A piece of sod is grass over thatch over a ~¾″ soil layer, laid on a tilled 4–6″ bed. Lay the longest straight edge first, stagger the seams like brick, and butt pieces tight — no gaps, no overlap — then roll and water.
Frequently Asked Questions
How many square feet does a cubic yard of mulch cover?
About 162 sq ft at 2 inches deep, 108 at 3 inches, and 81 at 4 — the depth decision is the whole estimate. Beds want 2 to 3 inches; anything deeper starves roots of oxygen and invites fungus. The mulch calculator converts your beds to yards or bags at your chosen depth and shows the bag-count equivalent.
How many bags of mulch equal a cubic yard?
A cubic yard is 27 cu ft, so it takes 13.5 standard 2 cu ft bags or 9 of the 3 cu ft size. Past roughly a yard and a half of need, a bulk delivery usually wins on effort alone — that is 20-plus bags to load, haul, and empty. The calculators show both formats so you can compare where the crossover lands for your project.
How many tons is a cubic yard of gravel?
Most crushed stone and gravel runs 1.4 to 1.5 tons per cubic yard; river rock and decomposed granite trend slightly heavier. Suppliers sell by the ton, so the gravel calculator does the yards-to-tons conversion by material and adds compaction allowance when the gravel is a base layer rather than a decorative topping.
How deep should gravel be for a walkway or driveway?
Decorative ground cover: 2 to 3 inches over fabric. Walkways: about 3 inches of compacted crushed stone. Driveways: 8 inches or more, built as two or three compacted lifts with larger stone at the base and finer on top. Remember compaction eats roughly 20 percent of loose depth — order against placed depth, which the calculator handles. The gravel depth diagram shows compacted depth by use — walkway, driveway, road.