Top 10 Soil Amendments for Organic Gardens

By Amy Grant | August 20, 2016
by Amy Grant
August 20, 2016

If you are starting a new planting bed, unless you are very lucky, your soil may not be quite up to par. It may be too sandy or too clay laden, in which case you need to amend the soil. Soil amendments are materials that are blended in with existing soil to augment its properties. They help to lighten clay or rocky soils or add body to sandy soils. They can also be used to alter a soil pH, aid in water retention and generally improve overall soil tilth.

Soil amendments are either organic or inorganic. Here are 10 soil amendments for organic gardens.

  1. Straw
  2. Sawdust
  3. Wood chips
  4. Grass clippings
  5. Sphagnum peat
  6. Compost
  7. Manure
  8. Worm castings
  9. Coffee grounds
  10. Biosolids

The first five organic amendments are often added to soil to lighten it and aid in water retention. Sphagnum peat is added to sandy soil, but the downside is its renewability and higher cost than that of others.

Both compost and manure are wonderful organic soil amendments. Manure, however, should be aged for at least a year and composted if used on fruits and veggies, lest the fresh manure burns plant roots due to its high ammonia content. Compost can be made yourself or purchased and promotes microbial activity in soil.

Versatile worm castings are probably just as good as compost and can be used as side dressing or tilled right into the soil.

Coffee grounds are a great addition to soil, especially around acid-loving plants.

Lastly, among the organic options is biosolid. Biosolids, or sewage sludge, contains 5-6% nitrogen by volume. They can either be purchased at gardening stores or obtained from some sewer treatment facilities.

Compost is definitely the best option for use as a soil amendment, especially if you make it yourself. This saves you big bucks, along with reducing waste and promoting healthy, organic gardening.

This article was last updated on
Read more about Top of the Crop
Did you find this helpful? Share it with your friends!

Browse Dozens of Our FREE Gardening Guides Today

Whether your dream garden is a houseplant sanctuary, a bountiful vegetable garden, a pollinator paradise, a bright and bold flower bed, or a backyard oasis – Gardening Know How has the perfect gardening guide just for you.

Click the button below to access more than 3 dozen of our completely free and completely comprehensive guides to growing your dream garden.

Join Us - Sign up to get all the latest gardening tips!