Composing Compost

By Joan Neiman-Agapas, Master Gardener, SCMG

Why do gardeners call compost ‘Black Gold“?

Because it is ALIVE with millions of beneficial organisms which improve the health of the soil – bacteria, fungi, & assorted micro-organisms.

Compost works to improve any kind of soil.  It increases sandy soils water & nutrient holding capacities.  It makes heavy clay soil more open & thus easier to work.

The slow release action of the compost over a longer period of time is advantageous.  Plants receive small, but consistent doses of nutrients to promote strong growth & vigor.

Best of all – it’s FREE as the raw materials come from your kitchen & yard. And, you can feel virtuous about keeping excess material out of the waste stream.

As with most things in life, there are a few rules to ensure successful compost.  These are more “guidelines” versus the “Ten Commandments,  but there area few ‘thou shalt nots’.  More about those later.

Raw material for the composter include:

From the kitchen:  fruit scraps, vegetable trimmings, crushed egg shells, tea bags, coffee grounds + filter, shredded paper

From the garden:  leaves (chopped up), grass (not too wet or chemically treated), soft stem plants (without seeds), old potting soil

Other:  Sawdust & wood shavings from untreated wood.  Wood      ashes from untreated wood can be added in small amounts.

Thou shalt NOT include:

  • Meat, fish or bones
  • Fats or oils (salad dressings, mayonnaise)
  • Dairy products/cheese
  • Rhubarb leaves as they contain chemicals that inhibit soil organisms
  • Plastics
  • Metals
  • Pet waste


To make your compost break down more quickly:

  • Chop material into smaller pieces to promote faster decomposition
  • Cover food waste with soil/dry leaves to discourage flies

Think lasagna & try to alternate layers of green & brown material, each about 2- 6 inches deep.  Greens supply nitrogen & provide heat to the pile.  Comes from the kitchen.  Browns supply the plant material (fuel) to the pile.  Comes from the garden/yard debris. Try to end with a brown layer on top   to discourage flies. Composter contents should be moist ie like a wrung-out sponge.  If the pile becomes too dry, moisten with enough water to regain the right degree of moisture.


Siting the Composter

There are many sizes/shapes/price points for commercially available composters.  Or, you can build your own three-bin unit.  There are lots of ‘how to’ videos available.  Size matters – bigger is better to ensure compost reaches a suitable temperature.  Minimum size = one cubic metre.

Place the composter in a sunny to partially shaded location, not too near the house.  Ensure ground is flat & level, with good drainage.


Is It Done Yet?

Depending on the material used, the composting process can take from    two month to two years.  Regular stirring/turning of the contents, together with a good balance between wet/dry material, chopped into small pieces will hasten the decomposition process.  Finished compost is dark in colour, crumbly with an earthy smell.  Think chocolate cake mix in consistency.

When ready, just spread over your garden, no need to dig it in, weather & worms will do the work for you.

Benefits of using compost include:

  • Increases soils’ organic matter content
  • Increases soils’ moisture holding capacity
  • Improves soils’ porosity
  • Helps control soil erosion
  • Enhances plant/flower growth by promoting strong root structures.


For more information on composting go to: