How to Add Organic Matter to the Soil


Poor soil is unsuitable for most of the plants you want to grow in your garden, whether they are ornamental or vegetable crops. Even good soil benefits from fresh amendments. Organic matter adds both soil nutrition and better moisture holding capabilities to your garden beds. Organic matter turns sandy soil into a richer gardening bed and helps loosen clay soil so plants can grow healthy roots in it. There are many choices in organic amendments, ranging from peat moss and compost to sawdust and bark.

Step 1

Lay a 3- to 5-inch layer of wood chips or peat moss onto garden beds if clay soil is an issue. Till it in with a power tiller to a depth of 18 inches. This loosens the soil and aids drainage in the clay.

Step 2

Apply a 3- to 5-inch layer of mature compost on top of sandy soils. Till it in to a depth of 18 inches. This aids moisture retention and soil nutrition in the sandy soil.

Step 3

Add a 2-inch layer of compost onto healthy garden beds each spring. Till it in to a 10- to 12-inch depth with a power tiller, or turn it into the soil with a shovel.

Step 4

Place an organic mulch around the flowers or vegetables after planting, such as bark or compost. Mulching preserves soil temperature and moisture, as well as adding nutrients to the soil as it breaks down.

Step 5

Amend potted plants with organic matter each spring. Lay a 1 to 2 inch layer of mature compost on top the soil to act as a mulch. The compost nutrients also leach into the potting soil with each watering.

Tips and Warnings

  • Only use aged animal manure that is thoroughly composted, otherwise it may damage or kill the plants. Do not add sand to clay soil, it makes the soil cement-like.

Things You'll Need

  • Power tiller
  • Shovel
  • Peat moss
  • Wood chips
  • Compost
  • Bark mulch


  • Colorado State Extension
Keywords: organic soil amendments, improving soil, organic mulches

About this Author

Jenny Harrington is a freelance writer of more than five years' experience. Her work has appeared in "Dollar Stretcher" and various blogs. Previously, she owned her own business for four years, selling handmade items online, wholesale and via the crafts fair circuit. Her specialties are small business, crafting, decorating and gardening.