Compost

In simple terms

Compost is what you get when leaves, grass and other organic material break down completely. It looks like rich, dark soil and feeds plants while helping soil hold water and air.

In depth

Finished compost is stable, fully decomposed organic matter teeming with beneficial microbes. Worked into native soil it improves both clay and sandy soils: it opens up tight clay for drainage and root growth, and helps sandy soil hold moisture and nutrients. Typical use is a 1–3 inch layer tilled into the top 6–8 inches of bed, or as a thin top-dressing on lawns. Unlike mulch (which sits on top to suppress weeds and retain moisture), compost is incorporated to amend the soil itself.

Why it matters

Compost is the single most effective amendment for the region’s heavy clay — it builds living, well-draining soil that grows healthier plants with less water and fertilizer.

Common mistakes

• Using unfinished or "hot" compost that can burn plants or rob nitrogen as it finishes decomposing.
• Treating compost as mulch — it works best mixed into soil, not left as a thick surface layer.

Examples & uses

• Amending garden and vegetable beds before planting.
• Top-dressing lawns to build soil.
• Blending with topsoil for raised beds.