As I mentioned in my first post of the new year, one of my goals for 2018 is to wrap my head around composting. In our vegetable garden, we're following a mixture of square foot and no-dig gardening, both of which call for large quantities of compost on a regular basis. Last year, we rented a car and picked up loads of free compost from our local council. Not only does the need to rent a car negate the benefits of "free" compost, it wasn't particularly good compost. It was full of large chunks of wood and little bits of plastic. A year later, I'm still pulling brightly-colored bits out of the vegetable bed every time I go out to harvest or weed. So, to take matters into my own hands, I bought myself a copy of How to Make and Use Compost by Nicky Scott and started looking for ways to make more compost, and faster.
In brief, composting involves two separate processes. First, aerobic bacteria colonize the waste heap and break down organic matter, causing the compost to heat up. Ideally, it produces enough heat to kill of weed seeds and pathogens. As the bacteria finish their job, the heap cools down. Then, worms and other critters move in, improving the texture and adding beneficial bacteria and enzymes from their digestive tracts.
As someone who works with centuries-old books on a daily basis, I'm all too aware that pretty much all organic matter tends to break down unless you take precautions to stop it. Consequently, for the past few years, we haven't really paid much attention to what went into our compost heap. If it was organic (as in, previously-alive, not as in organically-farmed), it went in the heap.*
This more or less worked in the sense that we didn't send our kitchen scraps to the landfill, but our "compost" never produced any noticeable amount of heat, so we probably just ended up with a very large worm bin. Which is awesome. We need all the worms we can get.** But worms are slow to break things down. To speed things up, we need to find a way to encourage our compost to go through the first, bacteria-driven stage.
The good news is, as with lacto-fermenting, brewing, bread baking, etc., the bacteria in compost are generally happy to get on with the job if you just give them reasonably pleasant working conditions. For composting, that means a 50-50 mixture of nitrogen-rich "greens" (like kitchen scraps and grass clippings) and carbon-rich "browns" (like woody twigs and hedge trimmings). Everything should be moist (not a problem outdoors in the UK), but with little air pockets everywhere. Without air pockets, aerobic bacteria give way to anaerobic bacteria that tend to produce smelly, fermenting sludge.
In a situation like ours, where we have a relatively small garden without trees or hedges, we produce a lot of greens but almost no browns. We live two doors down from a small strip of woodland and could technically try picking up twigs and branches from there, but the woodland is privately owned and actively managed, so I'm reluctant to disturb anything there.
What we *do* have in abundance is paper. When we moved from Scotland to Wales, we hired a professional moving company who carefully wrapped our vast quantities of kitchen stuff in paper. Two years later, we still have a massive pile of that paper, which we occasionally feed it to our worms. If we eventually manage to go through all of that paper, we get a free weekly local newspaper. And if that turns out not to be enough, there's always a few copies of the Metro in the break room at work. Once you start looking, there's plenty of carbon to go around.
Unlike the more traditional wood chips, twigs, or hedge trimmings though, paper becomes rather floppy when wet, collapsing all those little air pockets that we want. Cardboard does a slightly better job of holding its shape, and it's another thing we have in abundance. Not only do we still have plenty of cardboard boxes from our move, we get a fresh supply every time we order from Suma Wholesale (the hippy equivalent of Costco).
One other compost ingredient that holds its shape well is eggshells. In addition to making lots of good air pockets, eggshells also contain plenty of calcium, which is good for the garden in lots of ways. In gluten-free baking, eggs are often used to hold everything together, so after going (more or less) gluten-free, our egg consumption went way up. And you know what else comes with eggs? Cardboard cartons.
So, we've addressed structure and carbon-nitrogen balance. That leaves the problem of turning our compost. Turning compost isn't strictly necessary, but it will heat up more and break down faster if you do. Since our goal this year is to get a hotter, faster compost heap going, it seems like something we ought to try. The trouble is, in a household of two people both living with depression and digestive issues, our energy levels are wildly unpredictable and occasionally nonexistent.
We know from our previous years' experience that we simply aren't going to go outside and turn our compost heap with a digging fork. It's heavy and awkward and occasionally smelly, and we're almost always too tired. You can buy fancy compost bins on frames that allow you to rotate the entire bin, but they start at around £100, which runs counter to our goal of spending *less* money on the garden this year. When ordering a roll of garden fleece recently though, and I spotted an inexpensive compost tumbler on sale for just £7.50. Unlike its £100+ counterparts, this one wasn't a rigid bin on a rigid frame. It's basically just a heavy-duty duffel bag that you roll around on the ground. Lifting and digging may be more work than we can reliably commit to, but I think we can manage kicking something across the patio and back. At £7.50, I figure it's worth a try.
Assuming that all of the above works, our compost still needs some attention from worms before it's finished. Luckily, thanks to our previous years' kitchen scraps, we now have a very healthy worm population in our yard. Hopefully about once a month, we'll sift through the stuff in the roller. Any big chunks will go back in the roller, and small chunks will go into a heap on the ground where worms can get to it. Hopefully, by the end of this growing season, we'll have enough beautiful, finished compost to spread a fresh layer on top of our raised beds.
*Some composting guidelines tell you that you can't compost cooked food or meat. The truth is, you can compost anything that was once alive, but some things take longer or require a bit more attention to prevent them from have attracting flies, rodents, or other pests. A healthy compost pile can digest just about anything.
**When we moved in, our soil was pretty terrible. We're doing no-dig gardening in the backyard, but I dug a bunch of sand and compost into the front garden. As deep as a I could get the shovel and/or digging fork, it was clay so heavy and so pure that I was sorely tempted to throw some on the pottery wheel. More alarmingly, however, there was Not. A. Single. Worm. I almost cried when I saw how completely dead our soil was.
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