General questions on composting in Colorado - Ask Extension
1. From the perspective of farms or soil producers in Colorado, is there practical value in a stabilized 'pre-compost' material (material that has com...
Knowledgebase
General questions on composting in Colorado #925847
Asked March 11, 2026, 12:50 PM EDT
1. From the perspective of farms or soil producers in Colorado, is there practical value in a stabilized 'pre-compost' material (material that has completed the active thermophilic phase but is not fully cured), or do most agricultural uses require fully cured compost?
2. Are there specific standards or requirements farmers must follow when applying compost or outside organic material to fields (for example pathogen reduction standards, compost maturity, or testing requirements)?
3. What are the typical processing requirements or conditions that compost facilities must meet in Colorado for both pre-compost (post-active phase) and fully cured compost? For example: required temperatures, duration, pathogen kill standards, aeration, and moisture control.
4. Many modern compost systems can complete the thermophilic (active) phase in as little as 24 hours. How does this accelerated cycle interact with the commonly cited standard of 131°F (55°C) for three days? Would pre-compost from a 24-hour active cycle still meet the pathogen reduction expectations of farmers or typical agricultural regulations?
5. Which common commercial uses require fully cured compost (such as retail soil blends, nurseries, or certified organic farms), and which uses might accept less mature material like pre-compost (for example erosion control, land reclamation, or soil blending)?
6. Are there practical risks or limitations associated with storing or applying pre-compost that has not yet cured (such as phytotoxicity, nitrogen drawdown, or odor issues) that would limit its use? Are there any laws on the storage limit of composite that is still curing?
Denver CountyColorado
Expert Response
Thank you for reaching out to Ask Extension. I have put responses after each question in red. Many of the questions will best be answered by Colorado Department of Health and Environment. Contact information is below: 1. From the perspective of farms or soil producers in Colorado, is there practical value in a stabilized 'pre-compost' material (material that has completed the active thermophilic phase but is not fully cured), or do most agricultural uses require fully cured compost? Pre-compost would tend to draw down nitrogen and nutrients until it has been fully broken down. 2. Are there specific standards or requirements farmers must follow when applying compost or outside organic material to fields (for example pathogen reduction standards, compost maturity, or testing requirements)? Yes there are. Please see this resource. For further questions please contact: