Q. I want to build a better compost bin. Are there any designs that are "award winners"? If so, where can I find them?
- --- Don in Lawrenceville, NJ
The first is the classic "Lehigh bin" designed by J. I. Rodale, the founder of ORGANIC GARDENING magazine and the man who popularized composting in America. Working with researchers at Lehigh University back in the early 1940s, J. I. came up with a simple design for an open, contained composter that's close to perfect—a four foot square cube (four feet high, four feet deep and four feet long) made of cedar slats, designed to be stacked so that on each side, you have a cedar board, then an opening the width of a board, then another board, then another opening, and so on until the stack o' slats reaches four feet high. You drill holes into the edges of the boards at each corner and slide in four iron rods to hold everything stable.
The openings between each slat maximize the airflow that reaches the cooking compost while requiring much less wood than a solid-sided design. A properly made Lehigh bin can even be folded flat for transport and then opened up on site, like a cardboard box. The size was originally predicated on lumber lengths; you'd just have standard eight-foot boards cut in half, drill the holes and you're in business. But it was later discovered that the 64 cubic foot capacity was also perfect for making high quality compost. (Although larger is always better; a Lehigh bin made from eight-foot lengths of lumber would be a compost cooking monster!)
The other big DIY design is the classic 'three bin' system, where you essentially line up three Lehigh bins in a row, ideally rigged so that the fronts of the bins swing open. You toss your raw materials into the first bin until it's full, then fork it all over into the middle bin. When #1 is again filled up with raw material, you move everything over one bin. When #1 is filled the third time, the material in the last bin should be ready to use. The individual bins can be any size, and many designs incorporate side beams and roofs.
Scott Meyer, another former editor of ORGANIC GARDENING magazine, came on our show a few years back to promote a design the magazine was featuring that's a great improvement on the traditional three bin system—using hardware cloth or other tight fencing material in place of wood for much of the structure, dramatically improving the airflow and reducing the cost. And the good folks over at ORGANIC GARDENING were kind enough to put their original 'how to build it' article and images back up at their website. Here's the link. (Thanks, Eric at OG!)
Q. I would like to begin composting. Could you suggest a bin (one that comes ready to use, as opposed to something I'd have to make) and some reference materials? (I'm thinking of books by Mike McGrath.) Thanks very much.
- ---Iyana in Bala Cynwyd, PA
- 1) It's easy to read and tells you everything you need to make and use compost successfully.
2) A lot of the other compost books out there seem to be theoretical exercises by people who have never actually made black gold from their garden trash; and
3) You specified books by me so it's either that or tomatoes.
Open pile style: You can buy pre-made versions of the Lehigh bin; generally sold in easy to put together collections of parts where all you have to do is line up the slats and slide the rods down pre-drilled holes. There are also rolls of perforated plastic 'fencing' designed to be unrolled and filled with your raw materials. (This can also be achieved with any welded wire fencing, but the plastic 'roll your own' design has smaller openings that keep the raw materials inside better. I see this offered a lot at Master Gardener and Extension composting classes.)
'Sealed' composters are often a better choice when neighbors are nearby and you want to keep things neat and tidy, have a limited space in which to make your black gold, and/or want to include kitchen scraps and vermin are a concern.
There are many versions of basic backyard kind of styles. I personally have had great success with two different black recycled plastic units; both are readily available and have lids that lock to keep out playful vermin and a removable panel at the bottom that allows easy access to the finished material. Oh and both have open bottoms that allow entry to earthworms, who will then move the process along. 'The Earth Machine' is round; often offered at composting classes, it comes in two big pieces (plus a lid) and so doesn't ship or travel very easily. 'The Compost Digester', sold at retail and via mail order, is rectangular and breaks down into flat panels for easy shipping and transport. (And it's super easy to assemble; a true ten minute no-sweat job, even for those of us whose thumbs are barely opposable.)
And finally, there are the off-the-ground 'tumblers'. These are generally made of metal and have either one or two drum-shaped compartments. They're completely vermin proof and have a hand crank that allows you to turn the contents to move the process along faster. The lack of ground contact means you won't have earthworms helping you out, but if you keep the moisture levels right and remember to crank, you get a great finished product.