Top Tips for Successful Composting
The secrets of composting have been passed down in clandestine meetings in garden sheds for generations. Or, in simpler terms, you make a pile of organic matter, and it transforms into something beneficial for your growing areas. While any pile of organic matter will eventually turn into compost, there are a few simple considerations to ensure the process happens in a reasonable timeframe with minimal stress.
Diversity Leads to Resilience
This principle is one of my go-to answers for many challenges in an organic kitchen garden. It holds true for composting as well. If one method fails, having a contingency plan is always worthwhile.
This spring at River Cottage, we’re primarily composting in three ways: a thermophilic bay system, a wormery, and a bioreactor. Each approach has its benefits and drawbacks.
Thermophilic Bays: These are the quickest, taking as little as four weeks, and can handle large amounts of garden waste, which is essential during our busy spring clearance of overwintered cover crops. However, they require routine management, with waste chopped into smaller pieces before being added. We turn ours into the next bay every one to two weeks.
Wormery: This method produces beautiful, fine, nutrient-rich compost but can take longer to establish and cannot handle large volumes of waste simultaneously.
Bioreactor: This system generates fungally dominated, carbon-rich compost, ideal for mimicking the abundance of a forest floor, albeit in 12-18 months, and requires all materials to be assembled the same day.
The compost we use on our growing areas is a blend of all three, giving a diverse array of microorganisms a chance to enrich our soil.
Don’t Listen to All Advice
This may seem like an odd statement when sharing tips, but there’s an overwhelming amount of advice available. Thousands of blogs, books, and videos offer conflicting instructions on composting, which can be intimidating and may discourage people from even starting.
Different methods work for different people. Some will insist on a 3:1 ratio of brown to green waste by weight, while another source might recommend a 2:2:1 ratio of carbon-rich, nitrogen-rich, and a “biological activator” by volume. It’s no wonder many give up and head to the garden centre!
The truth is, there’s no one right way; every site and gardener is unique. It’s about distilling the kernels of truth from the advice available and figuring out why a method works before adapting it to your own site and working style. In our bays, we use a rough 50/50 mix of green (nitrogen-rich) and brown (carbon-rich) materials, built in layers over a few weeks. When one bay is full, we turn it into the next. But don’t follow that blindly, either!
Find What Works for You
In any endeavor, it’s rare to achieve incredible success on the first try. Since I began at River Cottage, our garden team has experimented with various composting methods. We started with large bays—6 feet square and 5 feet deep—but struggled to find the time to turn them. We built stacking sugi-ban frames, which made turning easier but were time-consuming to construct and could only handle one batch at a time. We also attempted to collect large amounts of materials in specific ratios and built piles in a single day, mixing green and brown ingredients fresh and monitoring closely. Although that method worked well, we had nowhere to store the next day’s garden waste during the process. The worm bin often fell into disrepair during busy periods or became overfilled and attracted flies.
Every trial led me to believe that simple, routine-based practices yield the best results. None of it happens overnight, but a little effort a few times a week accumulates into a functioning system. Now, our bays are straightforward—three 4ft pallets tied together with wire; they’re quick to build, easy to replace, and can be turned by one person in half an hour. We chop our garden waste as we collect it and add it to the first of four bays, incorporating more green or brown materials to maintain a good mix when needed.
There Are No Failures, Only Lessons
Learning from the mistakes of the last tip, it’s good to accept that any practice will change and improve over time. The way we’re currently composting won’t stay the same forever, and expecting 100% success will only lead to disappointment.
There are still batches which don’t break down as we’d like them to, or don’t get hot enough to kill off whatever weed seeds have found their way in. One batch full of couch grass might just do a good job filling in a trench made by a tractor wheel. Sometimes you don’t get compost in the timescale you want, just a rough top dressing to mulch a fruit bush or tree with, which is what I did when we moved some gooseberries last autumn.
The compost we make has improved, not because we went back to the drawing board and tried a new technique, but because we persevered with our existing approach, tweaked what was already working and dropped what wasn’t.
Get Nerdy
I’ve found that immersing myself in the process and enjoying it serves as better motivation than obsessing over specific criteria for success. With composting, I love that we have soil thermometers to monitor what’s happening inside the heap daily.
I’ve made it part of my morning routine to record data in a spreadsheet, plotting a graph of the pile’s temperature. This monitoring integrates composting into my gardening routine and the ecological cycle rather than isolating it from my other gardening tasks.
I’ve heard microscopy can also be a fascinating avenue, but I worry I might get lost down that rabbit hole if I’m not careful.
Another interesting aspect is the need for specialist seed and cutting compost, which is finer and drains better than standard compost, significantly impacting germination rates and the health of young plants. Naturally, River Cottage avoids unsustainable peat-based composts. We should aim for better alternatives than importing coir from the tropics. With this in mind, we’ve partnered with RocketGro, who creates composts using digestate from biogas production in our neighbouring Somerset. Their seed and cutting mix has yielded fantastic results this year and is fully organic certified!
