Convert bed measurements into bulk mulch yards and whole bags.
Before measuring bags, check several points in the existing bed. Record what remains and the additional depth you intend to buy. Do not enter the final combined depth as a new delivery.
Reproducible planning example: two 60 sq ft sections have different remaining layers. For a hypothetical chosen final depth of 3 in, one section with 1 in remaining needs 2 in added; the other with 2 in remaining needs 1 in. Enter two rows, 10 × 6 ft at 2 in and 10 × 6 ft at 1 in. Together they require 180 ÷ 324 = 0.555556 cu yd before allowance. Ordering 3 in across all 120 sq ft would instead buy 1.111111 cu yd. The final depth here is an arithmetic example, not a recommendation for every plant or mulch.
Organic mulch breaks down and may need replenishing; stone does not add organic matter through decomposition. UC IPM also emphasizes preparing the site and controlling perennial weeds before mulching. Compare mulch types and preparation guidance.
Do not automatically add a weed-barrier roll to the order. Compare fabric with a no-fabric plan before pricing it. Use the multi-area planner below for the two depths, then compare delivered bulk and bag totals.
Material-choice review: November 2, 2026. These are planning choices, not a site inspection or a drainage specification.
These are independent worksheets. Inputs do not transfer between them. Use the download button beside the result you want to keep.
Whole packages round up. Prices include only the items you enter. Delivery, tax and installation may be extra.
An existing bed and a bare bed can share an area but need different additional mulch. Measure what remains before entering new depth.
For a 20 × 5 ft bed, an arithmetic target of 3 in with 1 in of usable mulch remaining means 2 in to add. A bare bed needing the same chosen final depth needs 3 in. These depths illustrate subtraction, not horticultural recommendations; confirm the appropriate depth for the planting situation.
Original hypothetical scenarios for checking the arithmetic. Depths, conversion factors and buying increments are editable assumptions, not construction or product recommendations. The two cases are alternatives, not quantities to add.
Factor 1; extra 5%; bag yield 2 cu ft; bulk increment none cu yd; individual bags.
Factor 1; extra 5%; bag yield 2 cu ft; bulk increment none cu yd; individual bags.
Loading a case replaces the multi-area worksheet’s measurements and resets its prices to unknown. Save your own worksheet first. These buttons require JavaScript; all example quantities remain readable above.
At 5% extra and 2 cu ft bags, these orders are 9 and 14 bags. Check several places because an old layer may be uneven. If parts are bare and parts retain mulch, partition those areas into separate rows rather than applying the same subtraction everywhere.
Confirm mulch type and stated volume per bag. Keep planting openings and other intentionally clear areas out of the footprint. Do not use purchased surplus as a reason to pile material against trunks or building details.
Split differently depleted beds into measured non-overlapping zones.
Combine non-overlapping rectangles at different depths, subtract exclusions and round bags once for the total. All rows must use the same material. This worksheet is independent of the quick calculator above.
How to split an irregular area · How to compare a bulk quote with bags
Enter the additional depth you need, not the final depth if mulch already exists. The 2 cu ft bag yield is editable.
Length (ft): 16 · Width (ft): 12 · Material depth (in): 3 · Bag yield (cu ft): 2 · Extra material (%): 10.
These inputs produce 1.96 cubic yards to order. Change the measurements above to match your project.
Measure the exposed bed area, then check the existing mulch at several points. Enter the additional layer needed. Exclude places deliberately kept clear, such as planting openings. Different beds can have different additional depths, so use separate rows.
A 20 × 5 ft bed requiring 2 additional inches uses 0.6173 cu yd. With 5% extra, that is 0.6481 cu yd or 17.5 cu ft. At 2 cu ft per bag, the purchase is 9 bags. If only one additional inch is needed, the unrounded material requirement halves.
Topping up to a desired final depth is different from adding that entire depth. Existing mulch, decomposition and uneven distribution make a single ruler reading unreliable. A deep mound against a trunk should not be justified by a calculated remaining quantity.
Confirm mulch type, bag volume, bulk delivery minimum and available storage space. Keep your chosen landscape depth separate from the tool’s editable example. Spread to the planned layer rather than forcing every purchased bag into the bed.
Change bag yield from two to three. The bulk volume stays the same; only the rounded bag count changes.
It is a purchasing buffer for handling and irregularity. The planned installed depth remains the input you selected.
University of Maryland Extension: mulching trees and shrubs — Material and planting conditions affect depth. Avoid piling mulch against trunks.
YardTakeoff · Revised October 21, 2026 · Formula checks and scope · Report a calculation error