Compost management

On this page, you will find information on how to properly compost on your farm, how composting works, and how to access the rules and regulations regarding composting on-farm.

Why compost?

Composting provides farmers with multiple benefits and a pathway to convert farm by-products (ex. spoiled feed, manure, etc.) into a high-quality soil amendment. Some of the benefits that composting can provide includes, but is not limited to:

1. Final volume of compost is 40-60% of the original compost feedstock volume which results in lower hauling and spreading costs.
2. Composting stabilizes organic components that can be toxic to plants and nutrients that may be otherwise lost.
3. If high enough temperatures are reached and maintained, pests, weed seeds, and pathogens can be suppressed.
4. Odour is reduced, which can offer advantages for both storage and field application in relation to odour complaints.

How does composting work?

Composting is a controlled aerobic (requiring oxygen) decomposition of agricultural by-products. By understanding what a compost pile needs to thrive, it is possible to produce a high-quality soil amendment.

There are 4 key requirements to optimize the composting process:

1. C:N Ratio: The feedstock material must be well-mixed and have a balanced ratio of carbon (known as ‘browns’) and nitrogen (known as ‘greens’).
2. Oxygen: The composting process must be aerobic (have access to oxygen). It is required for the most time-efficient production of a high quality material and minimizes the release of unwanted and often odorous and harmful gases .
3. Particle size: The rate of decomposition increases with smaller particles because the amount of surface increases with smaller particles. However, smaller particles also reduce porosity and thus, air exchange. Good results are often obtained when the particle sizes range from 6 – 75 mm.
4. Water: Water is required to maintain the life functions of the microorganisms in the compost, however, excess moisture will reduce the airflow and the compost will cease to be aerobic. The optimal range is between 45 – 60% (feels like a damp or wrung-out sponge).

For more information on composting, please refer to the On-Farm Composting Guide below:

•  On-Farm Composting in British Columbia (PDF, 9.4 MB)

Compost management factsheets

Effective composting plays an important role in agricultural waste management by turning organic materials into a valuable soil amendment. Composting helps farmers manage waste responsibly, reduce greenhouse gas emissions, and improve soil health.

To support B.C. farmers and landowners in producing and using compost effectively, a new series of compost factsheets is now available. These resources provide practical information on:

• How to Begin On-Farm Composting (PDF, 840 KB) – Best practices for producing high-quality compost on farms
• Agricultural Feedstocks (PDF, 768 KB) – Suitable materials for composting and how to handle them
• The Composting Process (PDF, 582 KB) – Key stages and methods to ensure successful composting
• Using Agricultural Compost as a Fertilizer and Soil Amendment (PDF, 527 KB) – Using compost to meet crop nutrient needs responsibly
• Troubleshooting Common Agricultural Compost Problems (PDF, 440 KB) – Common composting challenges and how to address them
• Regulatory Requirements (PDF, 507 KB) – Understanding B.C.’s rules for agricultural composting

These factsheets are designed to help producers improve composting outcomes and meet provincial regulations while enhancing sustainability on their farms.

Assessing compost

Not all compost is created equal. Whether you are making your own compost or purchasing from a local facility, understanding how to assess compost ensures it’s safe, effective, and ready for use is incredibly important. Poor-quality compost can carry pathogens, weed seeds, or undecomposed material that harms rather than helps.

For more information on assessing compost, please refer to the Assessing Compost factsheet below:

• Assessing Compost Factsheets (PDF, 454 KB)

General regulatory requirements

There are two different regulations that impact the requirements of on-farm composting: the Code of Practice for Agricultural Environmental Management (AEM Code) and the Organic Matter Recycling Regulation (OMRR). The AEM Code applies when farms compost their own on-farm wastes with or without wood residues, whereas OMRR applies when farms compost imported wastes.

• For more information on composting under the AEM Code, click here.
• For more information on composting under the OMRR, click here.