Material Reference Data

Density and weight specifications for over two dozen garden materials.

MaterialDensity (kg/m³)Bag SizePrice/kgDescription
Topsoil1600 kg/m³40 kg$0.04Rich garden soil for planting
Garden Soil1450 kg/m³40 kg$0.05Pre-mixed gardening soil
Potting Mix750 kg/m³30 kg$0.09Lightweight indoor plant mix
Compost750 kg/m³25 kg$0.08Organic matter for soil enrichment
Manure900 kg/m³25 kg$0.06Natural fertilizer
Peat Moss400 kg/m³30 kg$0.12Soil amendment for acidic plants
Wood Mulch400 kg/m³20 kg$0.10Chipped wood for moisture retention
Bark Mulch450 kg/m³20 kg$0.11Shredded bark for landscaping
Straw Mulch80 kg/m³15 kg$0.15Light mulch for vegetable gardens
Fine Gravel1680 kg/m³25 kg$0.07Small decorative stones
Coarse Gravel1800 kg/m³25 kg$0.06Large drainage gravel
Pea Gravel1680 kg/m³25 kg$0.08Round decorative pebbles
River Rock1700 kg/m³20 kg$0.12Smooth landscape stones
Play Sand1520 kg/m³25 kg$0.05Clean fine sand
Coarse Sand1680 kg/m³25 kg$0.04Builders or paver sand
Perlite100 kg/m³10 kg$0.25Lightweight soil additive
Vermiculite110 kg/m³10 kg$0.28Moisture-retaining additive
Rubber Mulch650 kg/m³15 kg$0.18Recycled rubber for playgrounds
Pine Needles100 kg/m³10 kg$0.20Natural acidic mulch
Cocoa Hull Mulch250 kg/m³12 kg$0.22Premium chocolate-scented mulch
Lava Rock600 kg/m³15 kg$0.15Volcanic landscape rock
Crushed Stone1600 kg/m³25 kg$0.05Angular construction stone
Decomposed Granite1760 kg/m³25 kg$0.07Natural pathway material
Coconut Coir70 kg/m³5 kg$0.30Sustainable peat alternative

What Density Really Means

Density measures how much mass fits inside a fixed volume. Think of it this way: a cubic meter box filled with sand weighs far more than the same box filled with mulch, even though both occupy identical space. Understanding this difference drives smart ordering.

Why Gardeners Need to Know This

Garden materials vary wildly in density. Without accurate density numbers, calculations miss reality by factors of 5 or more. That translates to wasted money on over-ordering or project delays from running short.

Light Materials (Below 500 kg per cubic meter)

Easy to handle and transport. Perlite sits at just 100 kg per cubic meter, vermiculite at 110 kg, and peat moss at 400 kg. Wood mulch also falls into this category. These amendments improve soil without adding substantial mass.

Mid-Range Materials (500 to 1,000 kg per cubic meter)

Compost averages around 750 kg per cubic meter, manure slightly heavier. Rubber mulch also lands here. Manageable in bagged form but demands proper equipment for larger quantities.

Heavy Materials (Above 1,500 kg per cubic meter)

Mineral products dominate this range. Coarse gravel at 1,800 kg per cubic meter weighs more than a small vehicle in just one cubic meter. Delivery requires serious vehicles, and spreading demands more than manual labor for sizable jobs.

Factors That Shift Density

Water Content

Wet topsoil jumps from 1,400 kg per cubic meter when dry to 1,800 kg when saturated. Our reference table uses average moisture levels encountered at typical supply yards.

Packing Pressure

Gravel driven over repeatedly compacts 10 to 15 percent denser than loose material. When your project requires compaction, order additional volume to compensate.

Particle Dimensions

Fine particles nestle into smaller spaces, pushing density higher than coarse versions of identical material. Pea gravel weighs different per cubic meter than river rock despite both being stone.

Practical Applications

  • Pre-purchase planning: Apply density figures to calculate purchase weights
  • Transport logistics: Check vehicle load limits (most pickups handle 500 to 1,000 kg safely)
  • Cost anticipation: Heavier deliveries typically cost more to transport
  • Storage planning: Verify driveways and staging areas support expected weights

Smart Ordering Guidelines

  • Always round quantities upward to prevent mid-project shortages
  • Include 10 percent buffer for settling, spillage, and waste
  • Bulk pricing wins for any job exceeding 1 tonne total material
  • Request weight confirmation at pickup from your supplier
  • Bagged purchases win for small jobs despite per-unit cost premium