Did you know that more than 20% of the waste sent to landfill is organic? This is astonishing considering compost can be easily composted by anyone for free and the money spent on compost bags by people every day.
What about you? What is the proportion of kitchen waste in your bin?
From a wormery (Fig. 1) in an apartment to a compost bin (Fig. 2) in a garden, making good compost soil with kitchen waste has never been easier.
That said, many who tried have had some bad surprises; so here are some tips to avoid the main pitfalls:
- Adjust the quantity of waste to the quantity of worms you have. Start slowly and check how it goes. If it’s getting rotten before the worms touch it, add some paper, mix it all up so it’s aerated, and slow down for a week or two.
- Keep your compost in the shade to avoid compost getting too wet or too dry.
- The bigger, the better. More space as well as mixing accelerates the process.
- Try having around two volumes of paper for one volume of kitchen/garden waste. The objective is to respect a certain Carbon/Nitrogen ratio (Fig. 3). A well-balanced ratio for your compost is usually said to be around 25-30 (such as coffee grounds, dry grass, etc.).
- Nitrogen rich materials include fresh grass, green leaves (10-20), animal faeces (5-10), kitchen waste (20) and meat (1). They biodegrade very quickly and are good for bacteria.
- Carbon rich materials include dead leaves (50-60), straw (130), paper (300) and sawdust (250-500). They biodegrade slowly and are good for mycorrhizal fungi.
- Mixing up regularly accelerate the decomposition and prevent pest infestations and smelly compost.
- Putting meat and citrus in your compost is risky. The determining factors are the quantity of waste and the size of your compost (once a week in a 200L compost bin is preferable). Eggshells, bones, and feathers won’t do any harm but are usually not well biodegraded, so it is better to crush them down before.
- Avoid papers with ink or plastics on it. Paper bags, toilet paper rolls or egg boxes are perfect.
- Pet poo with litter is possible if the litter is compostable, and you are careful to respect the Carbon/Nitrogen ratio. Be careful to not use such compost in your garden before one year or two; in order to avoid contact with harmful pathogens.
- When possible have your compost heap directly on the ground. This will attract more biodiversity.
- Be patient. It usually takes 6 months to 1 year before getting a fine compost soil you can use.
If you have no compost bin or wormery, or if you don’t like worms, there are many other ways to compost. You could try:
- Surface compost: Throw your waste directly on the ground (how nature does). For aesthetic reason, you may want to cover it with some soil, straw, or dead leaves. Avoid doing this with meat (which may attract scavengers and flies).
- A compost tumbler (Fig. 4): Compost tumbler works with the help of aerobic bacteria. These invisible creatures will be the ones decomposing your waste. But, to ensure bacterial growth, it should be exposed to air regularly. This is why tumblers are smartly designed to be easily turned. The more you turn your compost, the faster it will mature. In warm countries, if turned daily, you can make compost within just a couple of months!
- A bokashi compost (Fig. 5): In Bokashi composting, kitchen scraps of all kinds are mixed with some bran, pressed into the Bokashi bucket, covered with another handful of bran, and tightly covered. When the bucket is full, it is set aside for twelve days. The mixture can be dug into a fallow patch of the garden or offered to someone with a compost bin. It cannot be used directly in the garden as it is too acidic, it would damage the plants roots).
- Making a compost ‘lasagna’ (Fig. 6) in a pot:
- Fill the pot with 1/3 of paper (to absorb the juice)
- Add 1/3 of kitchen waste
- Add 1/3 of garden soil
- Cover it up with some dry material (straw, dead leaves, grass clippings, etc.)
- Put aside for 6 months, and your compost is ready 😊
- Bonus: you can even plant a squash or a tomato plant in the pot during the process; they are usually happy with unfinished compost!
- Share your kitchen waste with neighbors, community centers or allotments. You can use ShareWaste to find local people who would be willing to accept extra scraps and compost it or feed it to their worms or animals.
Did you know that Portsmouth City Council will be trialing a food waste collection schemethis summer with 8,000 homes around the city?
Feel free to ask me your questions in the comment section below. I’d love to here from you!