At Purebred Compost, we believe in staying at the forefront of sustainable soil solutions. With multiple composting methods available, choosing the right system can make all the difference for the environment, your crops, and your bottom line. Today, we’re diving deep into three of the most common large-scale composting methods: Aerated Static Piles (ASP), Large Windrows, and Vermicomposting.
Let’s break it down:
1. Process Efficiency
Decomposition Rates:
ASP system have forced aeration and controlled airflow; ASP can finish composting in a year or two. Windrows, from 3 months to 2 years, depending on the conditions and machinery. While vermicomposting worms can convert kitchen scraps into finished compost in a few weeks, potentially taking as little as 2-3 months.
Labor Requirements:
Windrows demands more physical labor with regular turning, while ASP is semi-automated and has lower labor demands. Vermicomposting is labor-intensive upfront and during the harvesting of worm castings.
Energy Inputs:
ASP systems require blowers and sensors, increasing electrical needs. Windrows use more fuel and equipment for turning. Vermicomposting is low-energy but high-maintenance.
2. Scale and Capacity
Suitable Waste Volumes:
ASP and Windrows can process large-scale municipal and agricultural waste. Vermicomposting is better suited for smaller volumes or high-value niche markets.
Space Requirements:
ASP offers a compact footprint due to vertical layering and no need for turning. Windrows require ample horizontal space. Vermicomposting can be done indoors or in modular systems.
Scalability Potential:
ASP is highly scalable with modular aeration zones. Windrows can expand, but they need more land. Vermicomposting is scalable in controlled environments like ours.
3. Quality of End Product
Nutrient Content:
According to our Clemson lab analyses, Purebred’s ASP method consistently yields compost with high nutrient density, better than traditional windrows, and on par with high-quality vermicompost.
Maturation Time:
ASP: Up to 2 years, depending on the materials used, pile size, and how often the pile is turned.
Windrow: Typically takes between three to six months to mature, with some sources suggesting it can take up to a year. The exact time frame depends on factors like the type of materials used, the frequency of turning, and environmental conditions.
Vermicompost: It takes around 2 to 6 months to mature from initial setup to usable compost. The exact time frame can vary based on factors like the type of worms, the type and amount of waste added, and environmental conditions.
Consistency and Usability:
ASP creates a uniform, well-aerated product ideal for soil amending. Windrows can be uneven unless carefully managed. Vermicompost is rich and stable but limited in volume but a lot goes a long way. Our five-pound bags can last over a year or more for the average farmer, as a little goes a long way.
4. Environmental Impact
Greenhouse Gas Emissions:
ASP significantly reduces methane and nitrous oxide thanks to aerobic conditions. Windrows, if not turned correctly, can generate hotspots of anaerobic activity. Vermicomposting produces negligible emissions.
Types of Organic Waste Handled:
ASP can handle everything from food scraps, wood/ tree debris, and horse manure. Windrows are effective for green waste and manures. Vermicomposting works best with food scraps and paper-based materials.
Waste Management Challenges:
ASP allows Purebred Compost to tackle large-scale regional needs with precision and speed, reducing landfill dependence and supporting regenerative agriculture.
5. Cost Considerations
Initial Setup Investments:
ASP is the most capital-intensive. We’ve recently had to upgrade our pipe systems because the initial thin-walled pipes couldn’t withstand the pressure of heavier material loads.
Ongoing Operational Costs:
ASP costs more to run (electricity, monitoring), but offers labor savings and quicker turnaround. Windrows are cheaper to set up, but labor and fuel costs can add up. Vermicomposting is cheap to run but limited in revenue-generating scale.
6. Regulatory Compliance and Safety
Pathogen Reduction:
ASP systems meet pathogen-kill temperatures reliably with monitored heat zones. Windrows require diligent turning and documentation to stay compliant. Vermicompost rarely achieves necessary temps unless pretreated.
Standards Compliance:
Purebred’s ASP process meets and exceeds composting standards, allowing us to confidently sell to landscapers, municipalities, and gardeners alike.
7. Future Trends and Innovations
While composting is an ancient process, innovation is alive and well. At Compost 2024, we saw an exciting windrow bagging method that retains heat at the outer edges something that could enhance ASP systems by supporting more even and rapid decomposition.
Another trend we’re exploring biochar integration*. Adding biochar during the ASP process could supercharge microbial activity and boost carbon retention in soils.
*The process of incorporating biochar, a carbon-rich material produced through pyrolysis of biomass, into different systems or applications to leverage its benefits. This can include using biochar in soil to improve its health, integrating it into manure systems, or applying it in water filtration, biorefineries, and more.
After years of hands-on experience, we made the strategic decision to move away from the traditional windrow method. Our previous system often took years to fully compost material, requiring constant turning and taking up valuable operational space. It was time-consuming, costly, and inefficient. Today, we’re proud to use O2Compost’s Aerated Static Pile (ASP) system, which allows us to produce a more consistent, higher-quality compost in a fraction of the time, while maximizing the use of our composting area.
The Verdict
At Purebred Compost, we proudly operate with an upgraded ASP system and Vermicomposting because it gives us:
- Faster turnaround
- Better pathogen control
- A more consistent, high-quality product
- The ability to serve large clients and community needs
Whether you’re a farmer, landscaper, or eco-conscious homeowner, our compost is designed to enrich your soil and our process ensures we’re doing right by the planet.
Ready to grow with us? Contact us today to learn more about our premium compost and topdressing services.
We have switched from an ineffective windrow method to O2Compost’s Aerated Static Pile design. Our windrow method was taking years before the material was fully composted. Not only was it a time-consuming and costly endeavor to keep the large piles turned, but it also took up valuable space. Our O2Compost system helps us create a more consistent compost in less time and helps us maximize our composting area.