Compost vs Pea Gravel: Size, Cost, and Which to Use

Compost

Decomposed organic matter used as a soil amendment to improve soil structure, fertility, and water retention. Quality compost is dark, crumbly, and earthy-smelling. It adds beneficial microorganisms and nutrients that support healthy plant growth and improve poor soils.

Pea Gravel

Pea gravel is small, naturally rounded stone screened to 1/4 to 3/8 inch and washed clean. It costs $25 to $50 per ton in 2026, weighs 1.3 to 1.45 tons per cubic yard, and is the most popular gravel for patios, walkways, play areas, and garden beds because it is smooth underfoot and comes in warm mixed colors. The rounded shape is also its main drawback: the pieces do not lock together, so pea gravel shifts, spreads, and needs edging.

Compost

• ✓ Soil amendment
• ✓ Garden beds
• ✓ Lawn top-dressing
• ✓ Raised beds
• ✓ Tree and shrub planting
• ✓ Seed starting mix

Pea Gravel

• ✓ Patios
• ✓ Walkways
• ✓ Playgrounds
• ✓ Landscaping beds
• ✓ Dog runs
• ✓ Downspout drainage

Compost

• + Dramatically improves soil structure and fertility
• + Increases water retention in sandy soils
• + Improves drainage in clay soils
• + Adds beneficial microorganisms
• + Reduces need for chemical fertilizers

• − Quality and composition vary widely between sources
• − Can be odorous when fresh
• − May contain weed seeds if not fully composted
• − Too rich for direct planting — must be mixed with soil
• − Settles significantly after application

Pea Gravel

• + Smooth and comfortable underfoot
• + Warm mixed natural colors
• + Cheap at $25 to $50 per ton and sold everywhere
• + Drains fast, never muddy
• + Easy to spread by hand

• − Shifts and spreads, needs rigid edging
• − Ruts under tires
• − Hard to push a wheelbarrow or stroller through
• − Migrates into lawns and gets thrown by mowers
• − Does not pack, so it never firms up

Compost

Fine, crumbly texture when fully decomposed. Dark brown to black color. Should smell earthy, not sour or ammonia-like. Screened compost has been filtered to remove large uncomposted pieces. Mushroom compost is a byproduct of mushroom farming and is particularly nutrient-rich.

Pea Gravel

Pea gravel is naturally rounded stone screened to 1/4 to 3/8 inch, about the size of a garden pea. Because it comes from river and glacial deposits, a load is a mix of colors: tan, brown, cream, gray, white, and rust, with some regional loads running mostly one shade. It is washed, so there are no fines.