SumsibleMEASURE · ESTIMATE · PLAN
QUANTITY WORKSHEET / 03

Mulch / soil calculator

Calculate mulch or soil for multiple beds. Enter your additional depth and bag volume to see bags and bulk cubic yards.

How to use this calculator
  1. Measure the exposed bed, excluding occupied areas only where they will receive no material.
  2. Enter the additional depth to buy, not the total depth already in the bed. Select mulch or soil and check the bag volume.
  3. Read loose volume and rounded bags. Save separate products before reusing bed measurements.
Material quantity calculator

Your measurements

Units

Example values are loaded. Replace them with your measurements and product details.

Measurement method
Deduct a door, window or rectangle

Adds width × height × count to this area’s exclusions, per identical copy. Do not deduct it twice.

MATERIAL & ALLOWANCES

Material

Depth and bag volume are your choices. No planting or compaction allowance is assumed.

Measure the bed, then choose the fill

Mulch and soil both start with an area and a fill depth, but they remain different products. The material selector keeps these categories separate even when the same bed measurements are reused.

This worksheet estimates loose volume. Split irregular beds into rectangles and circles without overlap. The volume of each area is added before the bag count is rounded. The bulk result is also shown in cubic yards or cubic meters.

Bed volume = sum(net area × copies) × depth Adjusted volume = bed volume × (1 + allowance / 100) Bags = round up(adjusted volume / bag volume)

Understand the inputs

Material
Choose mulch or soil. This is a grouping identity, not a recommendation for a plant, growing medium or planting depth.
Depth
Enter the additional layer you intend to buy. If material already exists in the bed, do not inadvertently enter the total final depth.
Bag / order volume
The volume printed on your chosen bag or your bulk order increment. Volume is independent of how heavy the bag feels.
Allowance
A separate, user-chosen percentage. Settlement and compression are not automatically estimated from a material name.

Example: two small rectangular beds

Two beds measuring 8 ft × 3 ft each have a combined area of 48 ft². At a selected 2 in additional depth, they require 8 ft³ before allowance. With 0% allowance and a 2 ft³ bag, the result is four bags. If this becomes a soil estimate instead, reuse the dimensions but identify the soil product and check its bag volume separately.

Common estimating mistakes

  • Entering the full bed depth when only topping up an existing layer.
  • Counting an occupied footprint as empty fill space. Use the excluded-area field where appropriate.
  • Combining mulch and soil into one total because both are sold in cubic feet.
  • Reading a bag weight as its volume or assuming all bags are the same size.

What this estimate leaves out

No advice is given about depth around plants, settlement, soil composition, nutrient content or drainage. The volume model assumes a uniform layer in each estimate. It cannot represent a sloped bed precisely without dividing it into appropriate sections using depths supplied by the user.

Product information & references

Manufacturer and retailer volume tools are useful checks, but the dimensions and product volume entered here remain your assumptions.