Newspaper is generally acceptable for composting and provides a useful resource for balancing materials in a compost pile. Using old newspapers helps divert a common household item from the landfill while contributing to a healthy compost environment. Adding newspaper requires simple preparation steps and an understanding of which types of paper and ink should be excluded to ensure the resulting compost is safe and beneficial for the garden.
The Role of Newspaper as a Carbon Source
Newspaper is classified as a “brown” material because it is rich in carbon, which serves as an energy source for the microbes driving decomposition. This carbon helps balance high-nitrogen “green” materials, such as food scraps or fresh grass clippings. Microorganisms thrive when the carbon-to-nitrogen (C:N) ratio of the total mixture is maintained around 25:1 to 30:1.
The paper fiber is primarily composed of cellulose and lignin, which are carbon-based compounds that decomposers slowly break down. Shredded newspaper contributes to the physical structure of the pile, preventing dense materials from compacting. This bulk allows oxygen to circulate, which is necessary for aerobic decomposition and helps prevent foul odors. The dry nature of newspaper also helps absorb excess moisture from wet materials, aiding in regulating the overall moisture level.
Proper Preparation for Composting Newspaper
Effective composting depends heavily on preparation to ensure the material breaks down quickly and integrates fully into the pile. It is important to shred or tear the newspaper into smaller pieces rather than adding whole sheets or folded bundles. Reducing the paper to strips or small squares significantly increases the surface area available for microbial activity, which accelerates decomposition.
Adding the paper in bundles can block air circulation, creating anaerobic pockets that slow the composting process considerably. After tearing the paper, dampen it thoroughly, aiming for the consistency of a wrung-out sponge. This wetting step is important because dry paper will not decompose effectively and will instead remain intact. Finally, mix the prepared newspaper directly with nitrogen-rich materials to ensure the necessary carbon and nitrogen sources are available side-by-side for the microbes.
Materials to Exclude: Understanding Ink and Paper Types
While standard newspaper is generally safe for composting, certain paper types and inks should be avoided to prevent the introduction of harmful substances. Modern black and white newsprint ink is typically made with non-toxic, vegetable-based, or soy-based oils and carbon black, which are safe for the compost environment.
Caution should be exercised with heavily colored sections or glossy pages, such as magazine inserts or advertising flyers. Glossy papers and shiny advertisements are often coated with finishes that break down slowly or not at all. Heavy colored inks may contain pigments with trace amounts of heavy metals that could contaminate the finished compost.
Before adding newspaper, always remove non-paper components. This includes plastic wrappers, sticky address labels, or staples, as these materials are not biodegradable and will persist in the finished soil amendment.