Composting for allotments
Free soil food, less waste, better crops. Here's how to start and what you actually need.
Composting is the single best thing you can do for your allotment. It turns kitchen scraps and garden waste into dark, crumbly soil food that your plants will love. It saves you money on bought compost, reduces what goes to landfill, and improves your soil year after year.
The question isn't whether to compost — it's which method suits the way you garden. Here's the honest breakdown.
Affiliate links — This guide contains links to Amazon. If you buy through them, we earn a small commission at no extra cost to you. We only recommend things we'd actually use on our own plot.
Which method?
There are four main ways to compost. Most allotment holders end up with a cold bin or pallet bay — it's simple, cheap, and works. But if you want compost faster, or you're short on space, the other methods are worth knowing about.
| Method | Time | Cost | Effort |
|---|---|---|---|
| Cold bin / bay | 6–12 months | Free–£70 | Low |
| Hot bin | 30–90 days | ~£255 | Medium |
| Wormery | 3–6 months | ~£175 | Low |
| Bokashi | 2–4 weeks* | ~£40 | Low |
* Bokashi ferments waste in 2–4 weeks but you still need to bury it or add it to a compost bin to finish.
Cold composting
The simplest method. Pile stuff up, wait, and eventually it rots down into compost. “Cold” doesn't mean the bin is cold — it means you're not actively managing the temperature. Most allotment holders use this method because it works and requires almost no effort.
Pallet compost bay
FreeThree pallets stood on end, screwed together in a U-shape. That's it. The biggest capacity, the easiest to turn with a fork, and completely free if you can find pallets (ask local businesses or check Facebook Marketplace). Ideally build two bays side by side — fill one while the other finishes.
Line the inside with cardboard to stop compost falling through the gaps.
Blackwall Compost Converter (330L)
~£70The BBC Gardeners' World Best Budget Buy. A tidy black cone that looks neater than a pallet bay if your site has rules about appearance. Removable lid keeps rain out, and the dark colour absorbs heat to speed things up. Made from recycled UK plastic with a 5-year guarantee. Check if your council offers these subsidised — many do for £20-30.
Check your council website first — subsidised bins can be half the price.
Tumbler composter
£60–120A drum on a frame that you spin to aerate the compost. Faster than a static bin because turning is effortless — just crank the handle. Vermin-proof, which matters if rats are a problem on your site. Downside: limited capacity, and you can't add material continuously like a bay.
View on AmazonHot composting
Hot composting means actively managing the heap to reach 40–60°C internally. At these temperatures, weed seeds and pathogens are killed and the material breaks down much faster. The HOTBIN is the easiest way to do this without building and managing a traditional hot heap.
HOTBIN 200L
~£255An insulated bin that maintains 40-60°C internally, producing finished compost in 30-90 days — even in winter. You can add cooked food and small bones (unlike cold bins), and it kills weed seeds. The initial cost is steep but you'll produce more compost, faster, in less space than a cold system. The compost quality is noticeably better too.
Add a handful of shredded paper or cardboard with every food waste addition to maintain the carbon balance.
Compared to 6–12 months in a cold bin. Hot composting also kills weed seeds and pathogens, so the finished product is cleaner.
Wormeries
Worms eat your kitchen waste and produce two things: worm compost (vermicompost) and liquid feed. The compost is incredibly rich — a little goes a long way as a soil improver or potting mix additive. The liquid, diluted 10:1, is one of the best free plant feeds you can make.
Wiggly Wigglers Wormery
~£175The UK's specialist wormery company, run from a Herefordshire family farm. Their Urbalive wormery is well-designed, compact, and comes with everything you need including a worm voucher. The stackable tray system means the worms migrate upward as they finish each layer — you harvest from the bottom. Works indoors, in a shed, or outside in a sheltered spot.
Start slowly — add small amounts and let the worms establish before increasing. They eat half their body weight per day.
Bokashi
Bokashi isn't composting exactly — it's fermentation. You add kitchen waste to an airtight bin with special bran that contains microorganisms. After 2–4 weeks, the fermented waste gets buried in soil or added to a compost bin where it breaks down rapidly. The big advantage: it handles cooked food, meat, and dairy.
Bokashi bin starter kit
~£40A bucket with an airtight lid and a tap for draining liquid. You'll need two bins to keep a continuous cycle going — fill one while the other ferments. The liquid is a concentrated feed (dilute 100:1). The fermented waste needs burying in soil to finish composting, so it works best alongside a garden or allotment.
Perfect for flats with no garden — ferment indoors, then bury at the allotment.
Bokashi bran refill
~£8 for 1kgThe bran is the ongoing cost. A 1kg bag lasts about 2 months of regular use. You can make your own with wheat bran, molasses, and EM-1 solution, but the bought stuff is consistent and not expensive.
View on AmazonAccessories
You don't need much beyond the bin itself. But a couple of things make the process easier.
Compost thermometer
~£10A long-probe thermometer that tells you what's happening inside your heap. Essential for hot composting (you're aiming for 40-60°C), useful for cold composting to know if anything is actually going on in there. A 50cm probe reaches the centre of most bins.
View on AmazonGarden sieve / riddle
£15–25For sifting finished compost before use. Removes twigs, stones, and anything that hasn't broken down yet (chuck it back in the bin). A 37cm sieve with 9-12mm mesh sits nicely over a wheelbarrow. Bulldog make a good one.
Rest it on a wheelbarrow and shovel compost through — the finished stuff drops in, the rough stuff stays on top.
Compost caddy (kitchen)
~£15A small countertop bin for collecting food scraps before taking them to the allotment. Get one with a charcoal filter lid if you're worried about smell — it makes a real difference. Empty it every few days.
View on AmazonWhat goes in — and what doesn't
Greens (nitrogen)
- Vegetable and fruit peelings
- Grass clippings (thin layers)
- Annual weeds (before they seed)
- Coffee grounds and tea bags
- Crop waste and plant trimmings
- Comfrey and nettle leaves
Browns (carbon)
- Cardboard (torn up, uncoated)
- Straw and hay
- Dry autumn leaves
- Shredded paper
- Woody prunings (chopped small)
- Egg boxes and toilet roll tubes
Never add
Cooked food, meat, dairy, or fish (cold bins only — HOTBIN and bokashi can handle these). Perennial weed roots (bindweed, couch grass, ground elder). Diseased plants (burn them instead). Cat or dog waste. Glossy or coated card.