Improving Soil with Green Manures and Cover Crops

Beyond compost, green manures—fast-growing plants dug into the soil—replenish organic matter, fix nitrogen, suppress weeds, and improve structure. Used for millennia, they're a sustainable soil-building strategy.

Benefits of Green Manures

• Deep roots mine subsoil nutrients.
• Ground cover prevents erosion and compaction.
• Shades out winter weeds.
• Legumes (clover, lupin, mustard) host nitrogen-fixing bacteria.
• Boosts fertility, biological activity, and soil structure.
• Reduces nitrate leaching.

Practical Considerations

• Timing: Autumn-sown, spring-incorporated for quick organic matter; spring-to-spring for long-term erosion control.
• Patience required: Takes 6+ months to decompose. During breakdown, soil microbes temporarily tie up nitrogen—best on land resting for a season.
• Conditions for success: Well-drained, adequately limed (not acidic), warm soil.

While slower than compost, green manures deeply enrich soil over time. Ideal for vegetable beds between seasons or fallow periods.