Bulk Landscape Materials: Telling the Near Misses Apart

Almost nobody orders the wrong family. They order the wrong member of the right family: washed stone where a binding mix was wanted, a bedding sand where a crushed fine was wanted, fill where topsoil was wanted. On ground that swings from cherty Ozark clay to northern claypan to Bootheel silt inside one state, those near misses cost a season. Here are the pairs worth settling before you put a quantity in.

Base rock or clean rock: the fines decide it

Base rock is a 1 inch minus graded mix of crushed stone, gravel and binding fines, and it compacts into a layer a loaded truck can cross. Crusher run is the same idea at 3/4 inch minus, a tighter mix for pads and drives. Clean rock is the opposite: 1 inch clean is washed 3/16 to 1 inch angular stone with no fines at all, and 3/4 inch clean is the smaller washed size. Clean stone is for buried work, trenches, French drains, septic fields and bridging over fabric, where the voids are the product. It never sets up into a driving surface, and a binding mix never drains. Around here clean rock means washed only, so never use it for base rock or crusher run.

Driveway gravel or pea gravel on a lane

Driveway Gravel is a 3/4 inch graded crushed mix, angular enough to knit together under traffic, and it is what goes over a compacted base on a drive or a farm lane. Some quarries sell that surfacing grade as road rock by top size. Pea gravel is 3/8 inch and naturally rounded, which is exactly why it rolls under a tire and drifts to the edges. Keep it for play areas, patios and paths. For a garden route that has to stay firm underfoot, Walkway Gravel at 3/8 inch crushed is the one that packs.

Screenings or mason sand under pavers

Screenings are 1/4 inch minus crushed stone and dust, and they lock up when compacted, which makes them the leveling course over a compacted base on a patio or flagstone job. Mason Sand is ultra fine, washed and uniform, for masonry, joints and play sand. Washed Sand is the coarse one, for bedding, leveling and concrete work. Screenings are a crushed fine, not agricultural lime, and the two are not interchangeable.

Topsoil, garden soil or fill dirt in the same low spot

Top Soil is screened, balanced sand, silt and clay, and it goes in the top few inches where grass or beds have to grow. Garden Soil is a compost-enriched blend for raised beds and planting areas. Fill Dirt is compactable earth with minimal organic matter, and it is what raises a grade or fills a hole before anything else goes on. Build a low spot with fill, cap it with topsoil, and keep the garden blend for beds. They also weigh differently, which changes the order.

Rip rap or railroad ballast where water is moving

RipRap runs 4 to 12 inches and up, heavy enough to stay put where storm runoff is cutting a creek bank, a pond dam or a culvert outlet, and it is laid in a layer over a filter fabric sourced from a landscape supplier. Railroad Ballast is roughly 1 to 2.5 inch angular stone graded to interlock under load while draining, which suits a hard standing or a work route rather than a bank taking fast water. Drain Rock at 3/4 to 1-1/2 inch washed is the one for foundation drains and wall backfill.

River rock or large river rock in a dry creek bed

River Rock is 1 to 3 inch smooth, rounded stone in tans, grays and browns, for beds, borders and drainage details. Large River Rock runs 2 to 4 inches, which reads as a feature rather than a filler and holds better in a dry creek run that actually carries water after a storm. Both are decorative, not structural. Work out the tonnage for either on the river rock calculator.

The ones that do not have a twin

Six listings sit outside these pairs. #67, #8 and #89 Crushed Stone are the small washed sizes for joints and tight bedding, with 3/8 inch Crushed Stone for pipe bedding, and #4 Crushed Stone is the coarse open layer under a construction entrance. Shredded Mulch finishes the beds. Work the tonnage out on the material calculators before you set a quantity.

The calculator gives me a figure between two loads. Should I take the higher one?

A plan sheet calls for Type 1 base. Which product is that?

Is there a wrong time of year to put this material down?

How do I get a quantity for a bed that curves?