#### The Ultimate Guide to Composting #### Questions about composting? We've got you covered. #### Let’s start by breaking down the basics. One-third of all food in the U.S. is wasted, but that doesn't mean it should go to a landfill. What can't be recovered can be recycled into a nutrient-rich soil amendment called compost. What is compost? Compost is a nutrient-rich soil amendment that is created through the controlled decomposition of organic matter such as food scraps, yard waste, manures, and other organic materials.  When done correctly it looks dark, crumbly, spongey and has a mild earthy smell, similar to top soil. Combining the correct ratio of carbon-rich materials (browns), nitrogen-rich materials (greens), water, and air creates conditions for microorganisms, bacteria, fungi, and bugs to live. The movement and activity of billions of these microscopic creatures is what breaks down the organic material and heats the pile temperatures so that pathogens and seeds are killed off in the process. Compost is often used as a soil conditioner or fertilizer in gardening and agriculture because it improves soil structure, adds essential nutrients to the soil that plants need to grow, increases water retention, and enhances microbial activity. Compost also helps reduce the need for chemical fertilizers and reduces waste by keeping organic materials out of landfills. What are the benefits of composting? Composting has a wide range of environmental and social benefits beyond waste reduction. In addition to the environmental impact like increasing water retention, and suppressing plant diseases, industrial scale compost operations can generate twice as many jobs as landfilling and seventeen times as many as incineration. Composting at-home or through a service provider: • Keeps food and yard waste out of landfills, which are the third largest source of anthropogenic methane emissions. • Improves soil health, which supports higher crop yields without the need to use chemical fertilizers. • Rebuilds topsoil, which increases the grounds ability to sequester carbon emissions from the atmosphere. • Improves the structure of the soil which enhances water retention and means the ground is more resistant to drought. • Aids in reforestation, wetland restoration, and habitat revitalization efforts by improving contaminated and compacted soil. • Gets healthy soil into the hands of local famers and growers, which diversifies our food supply chains and ensures we have options when we eat. What is compostable? There's often confusion around this, because the answer varies depending on the method used to compost! **If you're composting at home or a community garden, the following items are typically considered safe to compost:** • Fruits and vegetables • Leaves • Yard waste or grass trimmings • Egg shells • Coffee Grounds • Tea Leaves • Dead house plants (non-diseased) • Non-glossy paper products like brown paper bags (best if shredded) **If you're composting with a service provider, or commercial compost facility you can often compost a wider range of material, including:** • The items listed above • All food waste including meat, dairy, bones and oils • Non-glossy paper, cardboard and paper towel rolls (including pizza boxes) • Paper egg cartons (not made from styrofoam) • Bamboo chopsticks and wood skewers • 100% cotton (cut into small pieces or shredded) • BPI Certified compostable products like coffee cups and cutlery • BPI Certified compostable packaging • BPI Certified compostable plastics It's important to note that your service provider or local facility may have additional rules about what they can and can't accept. These rules may be dictated by local regulations or in place to reduce contamination (like plastic), so it's important to familiarize yourself with the rules in your area. **Items that are not compostable:** • Plastic • Metal and aluminium • Styrofoam • Produce stickers and packaging • Items labeled "biodegradable" • Take-out containers (unless they are specifically labeled BPI Certified compostable) • Baby Diapers (there are no compostable baby diapers, and most facilities can not accept human waste) • Fireplace and BBQ ashes • Cigarettes and tobacco • Drug or vitamin pills • Dryer lint (most clothing is made with synthetic materials) • Black walnuts (poisonous to other plants) • Clam or oyster shells (basically rocks) What are the different methods of composting? These are the common methods of composting at home and at the bottom of this page are DIY resources for the common methods: **1. Aerated Turned Pile or Bin Composting (Common for Backyards)** The most common method for composting involves creating a small pile at a community garden or home backyard. The pile can be created directly on the ground, or in a bin. It's a particularly good method for breaking down yard trimmings and small amounts of food scraps. When properly created, maintained, and turned a backyard pile can produce compost in 3-5 months. **2. Vermicomposting (Great for Apartments)** Vermicomposting relies on a species of worms, red wigglers, contained in bins to feed on food scraps, yard trimmings, and other organic matter to create compost. The worms break down this material into high quality compost called castings. **3. Aerated Windrow Composting (Best for Larger Gardens and Farms)** Aerated, or turned windrow, composting is best for large volumes of food waste generated by entire communities or high volume food-processing businesses (e.g., restaurants, cafeterias, coffee shops). **4. In-Vessel Composting (Varies in Scale)** This method involves feeding organic materials into a drum, silo, concrete-lined trench, or similar equipment which allows good control of the environmental conditions such as temperature, moisture, and airflow. **5. Compost Service Provider (The Easiest Method)** If you don’t have the space, time, or resources to compost on your own, a compost service provider can be a great option for your household. **6. Community Compost Programs (Most Accessible if Available)** These programs are typically developed by municipalities or public entities and are open to the community at little to no cost. Does compostable material break down in a landfill? When compostable materials, like food scraps or compostable packaging, end up in a landfill, they do eventually break down over a long period of time. However, the decomposition process is much slower compared to a properly managed composting facility or home composting system. What is a commercial compost facility and how is it different than my backyard? A commercial compost facility, also known as an industrial composting facility, is a large-scale operation designed to process organic materials into compost on a larger and more efficient scale than what can be achieved in a backyard compost pile. Can I put my compostable plastic in my backyard compost pile? Even certified compostable plastics are not recommended for backyard piles. This is because these materials require high temperatures at a certain duration in order to break down completely without leaving any residue. How do I troubleshoot smells and issues with my compost pile? Your compost pile should have a spongey, fine, and crumbly texture and be dark brown or black. It should have a mild earthy smell, like soil. Bad odor and slimy texture are signs that your compost pile is not decomposing correctly, and may need to be adjusted or turned. How do I use compost in my garden? Compost adds nutrients to soils, suppresses plant diseases and pests, and aids in water retention among many other benefits. For raised garden beds, it's recommend mixing in compost with your choice of soil. Need more inspiration as to how to use compost? Check out these helpful resources: #### Still have questions? Let us know! If this page didn’t answer your questions about compost, email us at thedirt@compostnow.org.