Making the Most of Your Biotonne: What Can You Put In?

The golden rule: everything that rots naturally and hasn't been cooked or sealed off. In practice, this means for the household:

• Kitchen waste: fruit and vegetable scraps, potato peelings and eggshells, coffee grounds, tea bags (without clips), bread leftovers, baked goods and cut flowers.
• Garden waste: grass clippings, leaves, hedge and shrub cuttings, weeds, withered potted plants and small branches.
• Other: feathers, hair, unprinted kitchen paper towels, and small amounts of crumpled, unwaxed paper to act as absorbent lining.

Small branches and thicker bits are best chopped up beforehand so they rot away quickly in the composting plant. Soil only goes in small amounts along with roots — full flowerpot soil overloads the system.

The biggest trap: compostable plastic bags generally don't belong in the Biotonne. Even if a bag is labelled "compostable" or "biodegradable", the plant's fermentation process takes only a few weeks, while bags need considerably longer. They get screened out and end up in residual waste — just via the Biotonne on the way. Use newspaper or paper bags instead.

• Cooked meat, fish and bones: permitted or prohibited depending on the municipality — check your local waste calendar or organic waste ordinance. Some plants don't accept animal matter for hygiene reasons.
• Never: ash, vacuum cleaner contents, nappies, pet waste and cat litter, cigarette ends, treated wood and liquids such as oil or sauces.
• Also not: plastic corks, fruit stickers made of polyester and synthetic twine.

Smells and maggots are mainly caused by two things: moisture and leftover food sitting in warm weather. The following simple routine does the trick. Line the bottom of the bin with newspaper or cardboard — it soaks up moisture. Wrap wet kitchen waste in paper rather than tossing it in loose, and empty the kitchen Biotonne every day or two.

In summer, keep the bin in the shade as much as possible and always shut the lid — flies lay their eggs only if they can reach the waste. Empty it out briefly with a garden hose after each collection and let it dry; a splash of vinegar essence or a layer of rock dust on the floor neutralises odours. If maggots appear anyway: tip out the whole bin, wipe with vinegar solution and lay a thick layer of newspaper on the floor.

Winter brings a different problem: wet waste freezes to the base and sides, so you can't empty it fully. The collection crew may then leave the bin where it is. A thick layer of newspaper or cardboard at the bottom, regularly replaced, helps. Wrap wet kitchen waste consistently and, if frost hits, scatter some bird grit or sawdust between layers.

Also keep the lid clear of snow and ice so it can open. And don't worry if the bin is half-empty in winter: garden waste slows down so there's less to collect — but the collection rhythm stays the same, so remember to put it out anyway. By the way: many municipalities give away their finished compost free or at a discounted price in spring — a good reason to keep the Biotonne tidy all year round.

Whether cooked meat, natural-fibre litter or compostable bags are accepted is set out in your local organic-waste rules and depends on the process used by the composting facility in your region. Check your municipality's waste calendar if in doubt. BinMinder can send you a free reminder the evening before, so you never miss a Biotonne collection.