Compost Fundamentals

Compost Benefits & Uses

use of compost

Compost is ready for use when the temperature in the pile drops to the temperature of the surrounding air. Other signs are:

  • It smells earthy—not sour, putrid or like ammonia
  • It no longer heats up after turned or watered
  • It looks like dark soil
  • It’s crumbly, and doesn’t have identifiable food items, leaves or grass.

The pH is usually around 7.5, and it will have a C:N ratio ranging from 10:1 to 20:1.

Planting in compost before it is finished could damage plants. Undecayed carbon materials as wood chips or leaves uses nitrogen from the soil to continue decomposing, robbing it from the plants you grow. Undecayed nitrogen materials can harbor pests and diseases. Immature compost can introduce weed seeds and root-damaging organic acids.

Compost can be used in many ways in the garden. Coarse, semi-decayed woody material is suitable as mulch to put on top of the soil around the plants. It can be used as mulch around trees and shrubs, to keep the moisture in, to prevent weeds from growing around trees and shrubs. The decayed material is good for digging into the soil together with commercial fertilizers at preparation time.

It can be used for installing new lawns. A fine-screened layer can be used for a top dressing on established lawns. It can be used in the planting areas of landscapes. It should be used extensively in vegetable gardens to improve the organic matter content in the soil. It can be used for houseplants, for starting seeds in planting beds or flats, or made into a compost tea for watering plants.

Compost is also useful for erosion control. Erosion often is the end result of low soil fertility. Compost and the humus it contains can actually bind to the soil, building a good structure than encourages optimum fertility and erosion resistance. Studies have shown that a layer of compost works much better along newly planted hillsides beside highways than straw that was traditionally used.

An exciting new use for compost is bioremediation. Many things can contaminate surface waters, soils and reservoirs. Using compost can often restore these. The microorganisms in compost can sequester or break down contaminants in water or soil. Contaminates are digested, metabolized and transformed into humus and inert byproducts such as carbon dioxide, water and salts. Compost bioremediation is effective in degrading or altering chlorinated and nonclorinated hydrocarbons, wood preserving chemicals, solvents, heavy metals, pesticides, petroleum products and explosives.


economic aspects

testing and judging condition of compost

quality of composts

benefits of compost

use of compost

Why Compost | Biology & Chemistry | Compost Needs
Composter's Needs | Benefits & Uses | Conclusion

Return to Whatcom County Composting

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