Topsoil

Topsoil is stripped from the upper few inches of land where organic matter, minerals, and microbial life concentrate. Screened topsoil has been passed through a 1/2 in to 3/4 in mesh screen that removes rocks, roots, clumps, and construction debris, leaving a uniform, workable material suited to lawns and beds. Unscreened topsoil, sometimes sold as fill grade, skips this step and can contain stones up to 2 or 3 in along with roots and clay chunks. It costs less but is a poor choice anywhere fine grading or seed contact matters. Because the term topsoil is not strictly regulated, quality varies by supplier. Color and smell are decent field indicators, dark brown to black material with an earthy smell usually has good organic content, while gray, sandy, or foul smelling material may be low grade fill mislabeled as topsoil. When ordering bulk topsoil, ask whether it has been screened and what the source material was before committing to a large order.

Before spreading topsoil for a lawn or bed, clear the area of debris, existing dead turf, and large rocks, then loosen or till the subgrade a few inches deep so the new topsoil bonds rather than sitting as a separate layer that sheds water. For sod or seed, compact the loosened subgrade lightly before adding topsoil, since uncompacted subgrade lets the topsoil settle unevenly later. Spread topsoil in the depth appropriate to the project, from a thin 0.5 to 1 in topdressing on live lawns up to 8 to 12 in for vegetable beds, then rake it level and water lightly to help it settle. Expect 10 to 20 percent settlement after the first real watering or rain, so order extra material or plan a follow up topdressing pass rather than assuming the delivered volume is the final depth. Avoid driving delivery trucks or heavy equipment over soft or wet lawns when dumping material on site.

Compared with fill dirt. Fill dirt is subsoil with little organic matter, valued for compacting firmly under structures, patios, and grade changes. Topsoil is the fertile upper layer meant for plant growth and drains poorly under load. Use fill dirt for bulk elevation and structural fill, topsoil only for the finish layer where things need to grow.

Compared with garden soil. Garden soil is a manufactured blend of topsoil, compost, and often perlite, engineered to perform on its own in containers or raised beds. Plain bulk topsoil is not formulated for confined spaces and usually needs compost mixed in to avoid compacting hard. Choose garden soil for containers, topsoil by the yard for larger areas.

How much topsoil do I need. Multiply the length and width of the area in feet by the desired depth in feet, then divide by 27 to get cubic yards. One cubic yard covers about 324 sq ft at 1 in deep, 162 sq ft at 2 in, or 108 sq ft at 3 in. Add 10 to 20 percent extra to account for settlement after watering, since topsoil compacts down once it gets wet. For weight based ordering, expect roughly 1.0 to 1.5 tons per cubic yard depending on moisture.

How bulk topsoil is sold and delivered. Bulk topsoil is sold and delivered by the cubic yard rather than by the bag, which is far more economical for lawns, beds, or grading projects of any real size. Screened topsoil and unscreened fill grade topsoil are typically priced and sold separately, so confirm which grade a delivery quote covers before ordering. Because a moist cubic yard can weigh over 2,400 lbs, most orders arrive by dump truck rather than in a homeowner's pickup bed, and access for that truck should be planned ahead of a topsoil delivery.