Soil Improvement Basics: Liming, Humus, and Composting for Healthy Gardens

Why Lime?

Calcium from lime supports root and shoot development. It neutralizes soil acidity caused by leaching and improves clay structure (flocculation). Ground chalk is the preferred form—fine, concentrated, and slow to leach. Apply after digging, wait 4–6 weeks before sowing.

Building Humus

Humus holds nutrients in plant-available forms. Two types:

• Raw humus – Undecomposed material (grass clippings, acidic peat). Stimulates soil life but temporarily ties up nitrogen.
• Mature humus – Well-rotted manure, compost. Releases nutrients steadily.

Making Compost

Layer coarse material (straw), soft greens (kitchen scraps, grass), and thin soil. Keep moist, aerated. Avoid diseased plants, woody stems, and chemicals. A three-bin system provides continuous supply.

Using Manure

Only well-rotted manure. Fresh manure burns plants and smells. Poultry manure is high in nitrogen—best added to compost. Stable and farm manures improve all soil types.

Key Reminders

Never combine lime and organic matter simultaneously. Wait 3 months after adding humus before liming. Don't over-apply lime—it accelerates humus breakdown.