What is compost?
In a sense, compost is recycling. You take organic food scraps that would otherwise sit in a landfill, like apple cores or egg shells, and add “brown matter” (such as dried leaves) to speed up the natural process of decomposition. By helping it break down efficiently, you make the nutrients available to new plants, creating the ultimate sustainable plant fertilizer at little to no cost!
Why should I compost?
Adding this rich material can improve the structure or compostion of your soil, help to amend it from harmful elements like lead, and correct nutrient imbalances. Like people, plants need a proper balance of different "foods" to grow. The three primary nutrients they need are nitrogen, phosphorus, and potassium. The magic of compost is that we’re creating a substance that provides the right combination of these macronutrients so that plants can thrive. Healthy plants and increased fertility mean an even more productive season and a bigger harvest.
Considering that food scraps make up an incredible 30% of our landfills, composting is also an act of environmental sustainability. To be sustainable is to give back what you take from the planet – our shared global home. Composting helps to divert waste from landfills, reduce the use of petroleum-based fertilizers, and improve the soil for future generations of urban farmers.
The compost "recipe"
You should plan to mix roughly three parts brown matter (which is high in carbon) for every one part "greens" or food scraps (which are high in nitrogen), in alternating layers. For a visual demonstration of this principle, check out our video about the brown-green ratio:
Green matter can be weeds, fruit and vegetable rinds, crushed egg shells, grass clippings, tea bags, decaying hay, and even manure from your backyard chickens. Brown matter can be shredded cardboard or newspaper, straw, dried leaves, coffee grounds, wood shavings or sawdust, even dryer lint! Don't try to compost oily products or animal products like dairy or meat; they don't break down easily and can attract pests. You also want to avoid putting diseased plants in your pile so that the contagion doesn't spread to your other plants).
Cafes will often give you used coffee grounds for free if you ask nicely. You can get straw from farms or feed stores and dried leaves from neighbors after they rake their lawns. Jumpstart your compost pile by chopping up the brown matter really finely so that they break down faster. The faster your materials break down, the sooner you’ll have rich soil food!
Aeration and rat control
Many people that live in the city are concerned that open food waste sitting in piles will attract rats. You can use a compost bin with a lid, but it's more important to make sure that you cover green materials with dry brown matter so that the pile doesn't smell and doesn't get too wet. You also want to aerate the pile regularly by turning it or punching holes in it. Turning your compost will also help it heat up and break down faster. Learn more about how to keep rats at bay by watching our video.
It may take several months for your compost to break down into what looks like rich, crumbly black earth. To apply the compost to your garden, you'll first want to push it over a screen to strain out large pieces, rocks, etc. Then dump the sifted compost in the spot where you want it and rake it in! If you already have things growing in that area, you can add compost around the base of the plants using your hands or a trowel and gently incorporate it. This is known as "side dressing." The plants will still be able to draw nutrients from the compost nearby.