Our Certified Organic Compost is a premium-grade soil amendment designed to enrich your soil naturally while supporting sustainable land care practices. Produced using a Covered Aerated Static Pile (CASP) system, this compost is processed with precision aeration and microbial optimization to ensure clean, nutrient-rich, and contaminant-free material. Perfect for projects throughout Napa, Solano, Sonoma, and Marin counties, this compost is trusted by gardeners, landscapers, and agricultural professionals alike.
 
Screened for consistency and certified by the US Composting Council’s Seal of Testing Assurance, our compost is also OMRI listed and CDFA approved for use in organic agriculture. Whether you're revitalizing a home garden in Napa, preparing a vineyard in St Helena, or building soil health for large-scale landscaping in San Rafael, this compost delivers outstanding performance.
 
Key Benefits:
Enhances soil fertility and promotes beneficial microorganisms
Improves moisture retention for drought-resilient landscapes
Suppresses plant disease and weeds naturally
Supports erosion control and pollution prevention
Certified organic – OMRI listed, CDFA approved, and locally sourced
Sold per Cubic Yard
 
Coverage Per Cubic Yard:
~ 150 sq ft 2" depth
~ 75 sq ft 4" depth
Pro Tip: For best results, till compost into the top 6–8 inches of soil for planting beds or spread evenly as a topdressing. Order 5–10% extra to account for settling and grade adjustments.
 
Used across farms, vineyards, parks, and residential landscapes in Napa, Sonoma and Solano, this compost is a low-cost, high-impact alternative to chemical fertilizers—helping you grow healthier plants while reducing greenhouse gas emissions and keeping local organics out of landfills.
 
Order Certified Organic Compost today!
 
Delivery Service Areas
North Bay Materials delivers Certified Organic Compost to job sites, farms, and residential properties across Napa, Solano, Sonoma, and Marin counties, including:
Napa County – Napa, American Canyon, Yountville, St. Helena
Solano County – Vallejo, Benicia, Fairfield, Vacaville, Dixon
Sonoma County – Petaluma, Santa Rosa, Sonoma, Rohnert Park, Cotati
Marin County – Novato, San Rafael, Mill Valley, Corte Madera, Larkspur
 
 
Frequently Asked Questions – Certified Organic Compost
Q: What makes this compost “certified organic”?
A: Our compost is OMRI Listed and CDFA Approved for use in certified organic farming. It is produced without synthetic chemicals or additives and meets strict quality and safety standards through the U.S. Composting Council’s Seal of Testing Assurance program.
 
Q: How is your compost made?
A: We use the Covered Aerated Static Pile (CASP) composting method, which precisely controls airflow and temperature to optimize microbial activity, kill weed seeds, and ensure a mature, nutrient-rich final product.
 
Q: Can I use this compost for vegetable gardens?
A: Absolutely. Our compost is safe and beneficial for vegetable gardens, flower beds, fruit trees, vineyards, and lawns. It improves soil fertility and structure while introducing beneficial microorganisms.
 
Q: How is this compost different from regular topsoil?
A: Compost is an amendment rich in organic matter and nutrients, designed to improve existing soil. Topsoil, on the other hand, is primarily a planting medium and may lack the microbial life and nutrient density of compost.
 
Q: How much compost should I order?
A: Coverage is approximately 150 sq ft at 2" depth or 75 sq ft at 4" depth per cubic yard. For vegetable beds, we recommend incorporating 2–3 inches into the top 6–8 inches of soil.
 
Q: Do you deliver compost to my area?
A: We deliver throughout Napa, Solano, Sonoma, and Marin counties, including Napa, American Canyon, Vallejo, Benicia, Fairfield, Vacaville, Petaluma, Santa Rosa, Novato, San Rafael, and surrounding areas.
 
Q: Is your compost screened?
A: Yes. Our compost is screened for consistency to ensure easy spreading and blending with soil, making it suitable for both residential and commercial applications.
 
Q: Can this compost help with drought conditions?
A: Yes. By increasing soil organic matter, our compost improves moisture retention, reducing irrigation needs — a major benefit in the drought-prone North Bay climate.
 
Q: Is compost safe for pets and kids?
A: While our compost is natural and free of harmful chemicals, it should not be ingested. We recommend washing hands after use and supervising pets and children during application.