Keyhole garden with compost

What is composting?

Simply put, composting is the practice of creating compost.

This process recycles various organic materials (i.e. kitchen food scraps) otherwise regarded as waste products and produces a material called compost (technically ‘’humus’) that is like rocket fuel for your soil.

Carbon-rich materials ("browns")

  • Fall leaves
  • Spoiled hay / old straw
  • Wood chips
  • Twigs
  • Sawdust
  • Cardboard
  • Egg cartons and egg shells
  • Shredded newsprint and office paper
  • Shredded tree bark
  • Paper bags and paper towels

Nitrogen-rich materials ("greens")

  • Grass clippings
  • Fruit and vegetable scraps
  • Coffee grounds
  • Tea bags and tea leaves
  • Cut flowers
  • Soybean meal
  • Bedding from herbivorous pets
  • Poultry droppings

Experts suggest a 30:1 ratio of carbon to nitrogen organic materials when making compost.

The end result is a material we call “Compost”. It’s an organic nutrient-rich fertilizer that nourishes your soil and helps your garden grow.

What not to compost?

What? Styrofoam, glass or metal.

Why? They do not decompose.

What? Dog feces, used cat litter, and disposable diapers.

Why? They may spread disease and harmful pathogens.

What? Animal bones, fat, meat and fish scraps, greasy items, and dairy products.

Why? They encourage unwanted visitors like rodents.

Who benefits?


Composting is a wonderful, affordable (it’s free) and effortless way to recycle at your home.

Your soil

Compost improves soil structure, prevents the growth of weeds and regulates moisture in the soil. Compost fed soil uses up to 70% less water.

Your produce

Compost teems with microbial life – good microorganisms keep soil healthy and make nutrients readily available to growing plants. This means a bigger harvest and tastier vegetables.

Your planet

Composting minimizes methane emissions that contribute to climate change. It also acts as a natural fertilizer, reducing the need for chemical options, which can be harsh on the earth.

So how does the keyhole composting garden work?

Inspired by the African keyhole gardening technique, a Keyhole Composting Garden lets you compost household waste and grow vegetables in the same garden.

A central compost basket is used in the garden bed to conveniently place your daily kitchen scraps. This household waste then goes through the composting process and is transformed into food for your soil.

It all happens simply and conveniently in one place. It is the perfect solution for those who want to do less and grow more.

How do I start?

Start with healthy soil.

We advise that before you start composting, or planting, you create some healthy soil.

Let’s cook up some soil! - It’s as simple as brown, green, blue, brown, green, blue, brown…

You can use the cardboard packaging your garden arrived in!

Once the soil is ready, top it off with a layer of soil mix, plant your garden and begin the composting process. Simply deposit your daily kitchen scraps into the central basket of the keyhole composting garden.

How do I look after it?

You really don’t have to do very much. We advise you to turn the compost in your basket every 2 or 3 days to let air circulate and speed up the decomposition of organic materials. Make sure the pile does not get too damp. Any less water and the microbes can't thrive. Any more water and they will suffocate because air can't move as well.


If your compost basket smells sour or rotten you've probably got too much water and not enough air. If it smells of ammonia, you've got too much nitrogen ("greens") and not enough carbon ("browns").

No one wants rodents rummaging around their garden bed. This happens mainly due to the wrong materials being deposited. It’s important that you do not put meat or dairy in your compost basket. These materials rot quickly and the smell can attract unwanted  guests. We also suggest keeping your compost a little moist (as much as a wrung sponge), so it's not a place any animals would want to live.  Some gardeners use peppermint essential oil as a deterrent. Dilute it with water and spray it or drip the oil directly on the dry contents of your compost once a week or so.

A family of 4-5 people should be able to dispose of your household scraps daily, without filling up the basket.

Shredding or grinding organic materials is not essential, but it does help speed up the composting process. Egg shells are a material that many gardeners grind before disposing, as they can take a while to break down.

It's best in the shade because the compost is less likely to dry out: dry compost does not decay.

If you live in an area where temperatures remain above freezing your compost pile will continue to break down. If, on the other hand, you live in an area where temperatures fall below freezing for part of the year, the rate of decomposition will slow and if the nitrogen level is too low, the pile may freeze completely. In this case it may be worth composting seasonally.

Flies are attracted to rotting food on top of your compost. To avoid this, mix and bury your food waste within the existing material in your composting system, or add a layer of brown materials such as leaves, shredded paper, or sawdust on top of each layer of food waste.

Wastes from plant eating pets, such as horses, rabbits, gerbils, hamsters, guinea pigs or birds, can be safely composted at home. Just remember that all pet manures are “green” materials, high in nitrogen so they need to be balanced with “brown” materials. Waste from meat eating pets such as cats or dogs should not be composted for use in the garden because of the potential to spread disease.