You may have noticed in looking at pictures of my garden in this blog that I have several spin composters, also called barrel composters, rotating barrels or compost tumblers. At least online, gardeners either seem to love them or hate them. I love mine.
The reasons people say they don’t like them is because, they claim: 1) they smell; 2) they don’t hold much; 3) they get heavy when they get full, too heavy to spin. And more.
I would counter that spin composters aren’t the be all and end all of composting. They have their limitations and, once you realize those limitations, then they simply are another tool that is appropriate in certain circumstances.
I would say: 1) they don’t smell any more than any other compost pile if you have them correctly balanced “brown” and #green”; they hold half of the capacity of the container and, beyond that 3) they are too heavy to spin.
So, consider, if you have a 60 gallon composter, you can start with a minimum of 30 gallons of (undigested) compost, which will digest down to maybe a little more than half of that, 15 gallons — a good amount for a small garden. That’s a lot smaller than, say, a 4-foot by 4-foot fixed bin, but it’s not a fixed bin. Presumably, you bought a spin composted for quicker compost and the convenience of having it close to the garden or moving it where you want it.
I can attest that it makes good compost. I’ve had these for about four years. Mind you, I’m not saying that you shouldn’t have a fixed compost bin. Years ago, I had one compost bin made from wooden pallets wired together that was about 4-foot by 4-foot that I used for about 15 years and it just got better and better. I also used to just dump stuff in it and forget it. That’s fine, too.
At our farm, we had one big bulk pile out near the field where we dumped all manner of matter to be composted from a dump truck. If you are growing several acres, that’s the way to do it. You can turn it with a pitchfork or turning fork or with a tractor, if need be.
But if you only have a garden or small plot, a spin composter works fine. We had these four composters next to two plots where we grew greens: one about 2,500 square feet, the other about 800 square feet. (Note: we did not broadcast the spinners’ compost across the plots, like we did composted horse manure, which we dumped by the quarter ton to build up the soil; but we did use it to build up the rows where we tilled and planted.)
We put those spinners out there behind the house so we could have a place to put kitchen scraps and yard waste from those gardens without having to walk out to the field for the big pile. They fulfilled their function perfectly.
What I do is keep putting stuff in one until it is about half filled; then put duct tape across the top with the date when it was sealed, and continue to spin it once a week while I start filling and spinning another one. That way, I know when it will be ready (in 30 days or more from the date on the duct tape).
Since I have four composters, when they are all going, they are staggered so that I always have some compost, if I need it. It doesn’t hurt if you go over long on it. If you’re too short, you’ll notice when you open it (it will smell bad, or like ammonia, or items in it will not be digested, or it will still be hot).
In the fall, you can go heavy on falling leaves for the spinners if you’re planning on letting them overwinter until spring. These spinners had leaves in them from last fall.
Mix “brown” and “green” materials about equally for best results.
Green materials are what the term implies: fresh stuff, like vegetable food scraps, grass clippings, egg shells, coffee grounds, tea bags or leftover tea.
Brown materials are dry stuff, like shredded paper, wood chips, old leaves, etc.
Be careful what you put in them: nothing toxic (like sawdust from treated lumber or dead plants sprayed with poisons). Consider your compost bins like living beings. They are digesting material that you could not so that you can return to the earth the materials she produced to feed you and your family once again. It’s all a big Circle of Life.
Some advice: 1) err on the side of brown or dry, to avoid bad smells; 2) avoid manures. Yes, I know, manure (especially cow and horse manure) is great for the garden, but I personally would prefer to have it further from the house and also I would err on the side of caution in composting: longer composting time.
We always got our composted manure from a neighbor who kept horses; the manure was from a pile that had been mucked out the previous season: one full year of composting. (Note: If you are going be certified organic, there are specific rules that must be followed regarding compost, including records of ingredients used, turnings, and temperature readings outlined in Section 205.203(c)(2) of the NOP; rules regarding composted manures are quite stringent; for more info, see: http://tilth.org/certification/frequently-asked-questions/producer-farm-faqs).
Spinners are good for quick compost from household and common materials. Although some people say they can get good manure from a spinner in 15 days, I’d go 30 days minimum: raw compost can harm your crops, not to mention fail to digest weed seeds. Some people also suggest letting the first filling of the spinner sit for a week or so to allow it to heat up before starting to spin.
Thirty days is not gospel; it depends on the materials in the spinner (some items, such as limbs, may take longer), the ambient temperature outside (microbes that break down matter slow or even shut down in cooler temperatures), and the amount of matter to be digested, as well as whether it’s rotated properly, can affect the maturation of the compost. Moreover, materials may be too wet or too dry or clump up in the spinner (just keep spinning; it will break down; if too wet, add more “brown,” too dry, add more “green.”)
For bigger projects, if you have the space, in addition to the spinners, designate a back corner of the yard for longterm compost: such as tree limbs, manure, bulk waste.
Turn the barrel once a week, at least. It’s not the end of the world if you forget; but, presumably, you have a compost bucket in the house which you are emptying every day (to avoid smells, bugs, etc.), so presumably also you should be spinning your spinner, too.
In my opinion, some people get too uptight about compost. While it’s true that you want to err on the side of caution regarding manures, even the stringent National Organic Program standards don’t restrict adding raw plant material to your garden. If you’re just composting coffee grounds, newspapers, egg shells, leftover tea, newspapers and yard waste that you know hasn’t been treated with any chemicals, you should be fine. And spin composters can really help with that.
Jim PathFinder Ewing is a journalist, author, and former organic farmer now teaching natural, sustainable and organic agricultural practices. His latest book is Conscious Food: Sustainable Growing, Spiritual Eating (Findhorn Press). Find Jim on Facebook, follow him @EdiblePrayers or @OrganicWriter or visit blueskywaters.com.