Bark chippings calculator
Work out how much bark chippings a border needs, at the 50 to 100mm depth UK suppliers recommend.
Bark chippings calculator
Use your supplier's density
You need
- Volume
- Weight
- Area
| Order by | Exact | Order, rounded up for anything sold in whole bags |
|---|
Enter your measurements to see what to order.
One cubic metre of mulch weighs about 0.25 tonnes and covers about 13 square metres at 75mm.
How to work out how much mulch you need
- Measure the area in metres and multiply length by width.
- Pick a depth in mm and multiply it by the area to get a volume.
- Multiply the volume by the bulk density, 250 kg per cubic metre for mulch, to get a weight.
- Divide the weight by your supplier's tonne or bulk bag to get what to order, and round up. Suppliers do not sell part bags.
- Add 10 percent. Mulch settles and breaks down, and bags are rarely filled to the brim. Ten percent is the usual allowance.
How many tons in a cubic yard of mulch?
About 0.21 US tons, at 250 kg per cubic metre. Because published densities run from 200 to 300, the honest answer is a range: between 0.17 and 0.25 tons per cubic yard depending on grading and how wet the load is.
How many cubic yards in a ton of mulch?
About 4.75 cubic yards. One tonne is about 4 cubic metres.
How deep should mulch be laid?
| Use | Depth | What the supplier says |
|---|---|---|
| Border | 50mm to 100mm | Mainland Aggregates: bark used for mulching should be spread at 50 to 100mm depth. |
| Around trees | 50mm to 100mm | Mainland Aggregates. |
How much does mulch weigh?
Between 200 and 300 kg per cubic metre, a spread of 50 percent. Dry. Bark near 200 kg per cubic metre can roughly double after heavy rain, which puts a wet load above the top of this band. The calculator above uses 250, and you can replace it with your own supplier's figure.
3 published figures from 3 suppliers, read 2026-09-20.
| Supplier | Published figure | Condition |
|---|---|---|
| Sky Nursery (Shoreline, WA)US | 400-500 pounds per yard | unstated |
| Melcourt Industries LtdUK | Bulk Density 200 - 250 g/l | unstated (producer technical spec |
| Australian Native Landscapes (ANL)AU | Bark 0.3 (Tonnes / Metre) | loose ('Loose Tonnes' column) |
What you can order mulch in
| Pack | Where | Size |
|---|---|---|
| cubic yard | US, CA | 0.765 m3 |
| 2 cu ft bag | US, CA | 0.057 m3 |
| US ton | US, CA | 907 kg |
Mulch and mulch
In the US trade the same material is sold as mulch, ordered in cubic yards and tons, so the mulch calculator works in those units and at those depths.