Soil Amendments

Organic matter is the very heart and soul of organic gardening. Organic matter is the waste residues and remains of living organisms. As it undergoes the natural process of decay in the soil, it is converted gradually to a very stable form called humus. There are few things as important to garden preparation as adding organic matter to the soil. Ultimately, humus and the process by which it is formed can have a dramatic impact on your garden. So what’s the impact?

Synthetic fertilizers feed the plant, not the soil; and although they can provide the raw elements necessary for plant growth, they are a short-term solution that creates long-term problems; i.e., total dependency on chemical fertilizers, nutrient-depleted soil, and eventual vulnerability to insects and disease.

Synthetic fertilizers cannot replace organic matter lost through soil mismanagement. In time, more fertilizer is needed to compensate for the degeneration of organic matter in the soil.

The benefits of adding compost (organic matter) to your garden soil:

  • As compost is converted to humus in the soil, it will improve the ability of the soil to retain and release nutrients.
  • Organic matter helps to bind soil particles into aggregates, which produces a granular structure and permits the accessibility of air to roots, the capillary movement of water, and the penetration of roots through the soil. Ultimately it will help to make the soil easier to work.
  • Compost helps to improve the ability of the soil to hold water.
  • Compost provides a food source for the many beneficial soil microbes critical to a robust, vital soil.

It is important that compost or other organic matter be added to a garden every year to keep the soil alive. We suggest that 2 inches be added every spring and tilled in a minimum of 6 inches before planting. For new gardens, or poor soil, add organic matter again in the fall as a mulch for the first few years.

Soil Amending Chart
For 100 Square FeetSoil DepthYou will need:
6 inches54 cubic feet
4 inches35 cubic feet
3 inches27 cubic feet
2 inches18 cubic feet
1 inch9 cubic feet
1/4 inch2 cubic feet
1/8 inch1 cubic foot