Compost bins are among the most practical DIY projects on a homestead, converting kitchen scraps, garden waste, and livestock bedding into soil amendment. The scale ranges from single pallet bins handling household waste to multi-bin systems processing garden trimmings and animal manure.
Three-pallet bins are the simplest and most widespread design. Three wooden pallets are stood on edge and wired or screwed together at the corners to form a U-shape, with the open front allowing access for turning and removal. A fourth pallet or board across the front keeps the pile contained. The gaps between pallet slats provide natural aeration. Pallets made from untreated hardwood last 3 to 5 years in outdoor conditions.
Three-bin systems are built from lumber, concrete blocks, or welded wire mesh arranged as three adjacent compartments. The first bin holds fresh material, the second is turned partly decomposed material, and the third contains finished compost ready for use. Each bin measures roughly 1 cubic meter (35 cubic feet) to maintain adequate pile mass for thermophilic composting. The partitions between bins are removable slats or doors that allow material to be forked from one bin to the next.
Tumbling composters are rotating drums mounted on a frame, typically built from a 55-gallon plastic drum or food-grade barrel. The barrel is mounted horizontally on a stand of lumber or steel pipe, with a crank handle or hand wheel for rotation. A door cut into the side allows loading and unloading. Vents drilled into the barrel provide airflow. Rotation speeds decomposition to 3 to 4 weeks during warm weather compared to 6 to 12 months for passive bins.
Vermicomposting bins house red wiggler worms (Eisenia fetida) that process kitchen scraps into castings and liquid fertilizer. A typical DIY bin is a shallow tote or wooden box approximately 30 centimeters (12 inches) deep, with drainage holes in the bottom and a tight-fitting lid. Bedding consists of shredded newspaper or cardboard, and the worms are fed kitchen scraps buried in layers. Stacked-tray systems allow finished castings to be harvested by moving trays upward as the worms migrate.