Why Compost Deserves a Corner of Every Smallholding

If you keep a few hens, grow a bit of veg, or simply mow a lawn, you are already producing the raw material for next year's growing. Compost is the quiet engine of a productive smallholding: it turns waste you would otherwise burn or cart to the tip into a crumbly, sweet-smelling soil improver that holds moisture, feeds worms and saves a small fortune on bagged products. The good news is that making it well is not complicated. Get the balance of materials roughly right, keep the heap as damp as a wrung-out sponge, and turn it now and then. Within a few months you will have compost dark enough to disappear into your beds and borders.

Greens and Browns: The Balance That Drives the Heap

Everything that goes on the heap falls into one of two camps. Greens are wet, nitrogen-rich materials that heat the pile up and feed the microbes doing the work. Browns are dry, carbon-rich materials that give the heap structure and let air move through it. Get the ratio badly wrong in either direction and you will know about it quickly: too much green and the heap turns to slimy, smelly sludge; too much brown and it sits there cold and inert for a year.

As a rule of thumb, aim for two to three parts browns to one part greens by volume. That surprises most newcomers, who tend to heap in far more kitchen scraps and grass than the pile can cope with.

• Greens: grass clippings in thin layers, vegetable and fruit peelings, tea leaves and plastic-free tea bags, coffee grounds, spent annuals, nettles, comfrey, young weeds with no seed heads, and manure from herbivores such as hens, horses or rabbits.
• Browns: torn cardboard with the tape removed, newspaper, straw, hay, autumn leaves, woodchip in moderation, sawdust, egg boxes, loo roll tubes, and used hen bedding on straw or shavings.

If you are unsure, look and smell. A sour, slimy heap wants more cardboard and a good turn. A heap that never warms up wants a bucket of grass clippings or a watering can.

What to Add, and What to Keep Out

A compost heap is not a rubbish bin, and a few items will cause real trouble on a smallholding where rats, foxes and badgers are rarely far away.

• Leave out cooked food, meat, fish, dairy and bones, which attract vermin.
• Leave out perennial weeds such as bindweed, ground elder and couch grass unless you are confident your heap gets genuinely hot.
• Leave out diseased plant material, glossy magazines, cat and dog waste, and anything treated with a persistent weedkiller.
• Add with care grass clippings, which mat down into an airless layer; mix them with cardboard or straw rather than tipping in a thick wedge.

Crushing eggshells, chopping big stalks and tearing cardboard into palm-sized pieces all speed things up. The smaller the pieces, the faster the microbes get to work.

Building the Heap and Keeping It Working

Size matters more than most guides admit. A heap of roughly one cubic metre — about a metre in each direction — holds heat far better than a small bin, and is still manageable with a fork. Site it on bare soil or gravel so worms and drainage can do their work, and avoid the driest or wettest corner of the plot.

Build it in layers, like a lasagne: a few inches of browns, a thinner layer of greens, a sprinkle of soil or old compost, then repeat. Keep a bag of cardboard or straw beside the bin so you always have browns to hand when the kitchen caddy arrives.

Turning is where the magic happens. Fork the heap over every two to four weeks, moving the outside to the middle and the middle to the outside. You should see steam rise on a cold morning in the first fortnight. If you would rather not turn it, the compost will still form — it will simply take twice as long.

Moisture is the detail most people miss. Squeeze a handful: it should feel like a wrung-out sponge, neither dripping nor dusty. Cover the heap with a tarpaulin or a piece of old carpet in wet winters to stop it becoming waterlogged, and water it in dry summers. Cold weather slows everything down, but a well-built heap keeps ticking over all winter.

When It's Ready, and How to Use It

With regular turning and steady moisture, expect finished compost in three to six months through the warmer half of the year, and longer over winter. It is ready when the original ingredients are unrecognisable, the texture is dark and crumbly, and it smells earthy rather than sour. A few worms and woodlice in there are a good sign, not a problem.

If you want a finer product for seed trays, riddle it through a coarse sieve and chuck the lumps back on the next heap. Otherwise, use it straight:

• As a mulch — a 5cm layer around perennials, soft fruit and shrubs suppresses weeds and feeds the soil beneath.
• Dug in — spread a generous barrowload per bed in autumn and let the worms pull it down.
• In potting mixes — blend roughly one part compost with one part loam and one part grit or leafmould for a decent homemade growing medium.

Do not overdo it. Compost is a soil conditioner, not a fertiliser, and a little applied regularly beats a thick dump once a year. Start with one heap this season, keep the balance in mind, and you will wonder how you ever gardened without it.