Topsoil vs. fill dirt vs. garden soil
They all look like dirt on the truck, but they do very different jobs — and are priced very differently. Here's how to order the right one.
On this page
The short version
| Material | What it is | Use it for |
|---|---|---|
| Fill dirt | Subsoil with little organic matter; may include clay, sand and small rocks | Raising grade, filling holes, building up under patios and lawns |
| Topsoil | The fertile upper layer of soil, usually screened to remove rocks and roots | The top 4–6 in under new lawns, leveling, top-dressing |
| Garden soil / planting mix | Topsoil blended with compost or other organic matter | Flower and vegetable beds |
| Compost | Decomposed organic material | Mixing into beds, top-dressing lawns in thin layers |
| Raised bed mix | Light blend of soil, compost and often other ingredients | Filling raised beds and large containers |
Why fill dirt belongs underneath
Fill dirt is chosen because it compacts well and stays put: it has little organic matter to rot and settle over time. That's exactly what you want under a patio, a shed or when raising the grade of a yard — and exactly what you don't want for plants to grow in. Put fill in the lower layers, compact it, and finish with topsoil where things will grow.
How deep to use each
- New lawn: 4 to 6 inches of topsoil over loosened subsoil.
- Top-dressing a lawn: about ¼ to ½ inch of topsoil or compost, raked in.
- Garden beds: 6 to 12 inches of loose, fertile soil; mix compost into the top layer.
- Raising grade: fill in compacted layers of a few inches at a time, then topsoil on top.
Size each layer with the topsoil calculator — it includes fill dirt and compost as materials, with their typical weights.
Buying tips
- See it before it's dumped. Good screened topsoil is dark, crumbly and free of rocks, roots, construction debris and weed-filled clods.
- Ask about the source and screening. "Topsoil" isn't a regulated term; quality varies widely between suppliers.
- Buy by the yard when you can. Soil sold by the ton includes the weight of its water — wet soil can weigh a lot more for the same volume.
- Plan the drop spot. A few cubic yards is a big pile; tarp the driveway and have it dumped close to where it's needed.
Frequently asked questions
Can I use fill dirt for a lawn?
Not on its own. Grass struggles in fill because it lacks organic matter and nutrients. Use fill to build up the grade and finish with at least 4 inches of topsoil.
Is topsoil the same as garden soil?
No. Garden soil is topsoil enriched with compost or other organic matter for planting beds; it's usually too rich and loose for filling or leveling.
Does soil settle after delivery?
Yes, especially once it's raked and watered. Order about 10% extra, and fill low spots in layers.