How to Increase Organic Matter in Soil


Organic matter helps soil absorb and retain moisture and nutrients, resulting in more lush and healthy plant growth. Soils high in organic matter have a loose texture with a dark brown to black appearance. Don't lose hope if your soil is naturally devoid of high amounts of organic matter. Annual amending with basic garden compost can increase your soil's organic matter and improve the soil condition over time.

Garden Soil

Step 1

Break up the soil surface with a spade or, for larger garden plots, a mechanical rototiller. Loosen the soil to a depth of 6 to 8 inches until the soil has clumps 1/2 inch in diameter. Avoid tilling too finely.

Step 2

Spread 3 to 4 inches of compost over the surface of the soil.

Step 3

Mix the compost into the top 6 inches of soil with your spade or tiller. Repeat every spring before planting your vegetable garden or ornamental beds.

Lawn Soil

Step 1

Loosen the soil to a depth of 6 inches, using either a spade or a tiller, before planting your lawn.

Step 2

Apply 1/2 to 1 inch of compost on the dirt surface. Don't add more than this, advises Oregon State University, as greater levels of organic matter will result in an uneven lawn surface as the organic matter decomposes and the volume of the soil falls.

Step 3

Stir the compost thoroughly into the soil's top 6 inches.

Things You'll Need

  • Spade or tiller
  • Compost


  • "The Complete Compost Gardening Guide"; Barbara Pleasant and Deborah Martin; 2008
  • University of Illinois Extension: Compost Benefits and Uses
  • Oregon State University: Improving Garden Soils With Organic Matter
Keywords: increase soil matter, organic soil matter, boost organic content

About this Author

Josh Duvauchelle is an editor and journalist with more than 10 years' experience. His work has appeared in various magazines, including "Honolulu Magazine," which has more paid subscribers than any other magazine in Hawaii. He graduated with honors from Trinity Western University, holding a Bachelor of Arts in professional communications, and earned a certificate in applied leadership and public affairs from the Laurentian Leadership Centre.