Measured Tree Ring Mulch Top Up Bag calculator.
Top up measured annular areas from existing to supplied target depth, excluding the central circle. Does not recommend depth or trunk clearance.
Your inputs
Use measurements from your plan and properties from your chosen product. Any prefilled values are illustrative.
A clear estimate starts here.
Enter your dimensions and product details to see the quantity and purchase breakdown.
Formula and assumptions
How this calculation works.
Additional volume = π(outer radius² − inner radius²) × max(target depth − existing depth, 0) × count × allowance.
A worked example
Illustrative inputs only. Product properties and design dimensions are not recommendations for your project.
- Loose volume per selected bag
- 0.05 m³
- Your material allowance
- 0 %
- Measured outer diameter
- 2 m
- Supplied excluded central diameter
- 1 m
- Your supplied target depth
- 100 mm
- Measured existing depth
- 50 mm
- Identical zones
- 2
Top-up mulch bags: 5 bags
Equivalent uniform existing depth. Target depth and central exclusion are supplied, not horticultural recommendations.
Before you purchase
Use dimensions from your plan and properties from your chosen product. Any design spacing, section or fixing pattern must already be specified.
Measurements, product properties and application patterns are supplied by you. Illustrative examples do not recommend construction or planting specifications.
Method: dimensional arithmetic and user-supplied specifications. Software checks: 2026-10-05. Calculation and review policy.