Composting in urban settings

According to a research carried out in the US Environmental Protection Agency, kitchen scraps account for 27 percent of municipal solid waste, and organics in landfills are a potent source of greenhouse gases (see References 1). In the absence of a garden or backyard, even apartment dwellers can help reduce solid waste by composting on their balcony. Moreover, composting is also a valuable gardening technique that can provide our plants with all the nutrients needed to thrive. Composting on our balcony is very beneficial not only for our garden but also for the environment, it is hygienic and if done correctly will not cause any bad smell and will not attract any unwanted insects and parasites. This activity works with small, medium and big size groups.

Materials neededgreen-waste-513609_1280

  • medium/big size garbage bin, preferably with a lid
  • At least one drill, (hammer and nails are a possible alternative if a drill is not available)
  • Small branches, cardboard and/or dry leaves (enough fo cover the bottom of the bin)

Goal

Building a compost bin that can be easily, efficiently and effectively used in a flat, on a balcony, terrace, roof or in a small urban garden. Make the participants understand the importance of composting.

How to…

This practical activity is ideal to provide the participants with some basic information about composting and/or to complement a lecture focused on the importance of soil and compost in a permaculture garden.
The ideal size of the group is maximum 6-7 participants. If there are more people, building more than one garbage bin can be a solution. The trainer will show and explain what to do in front of all the participants and let them work on their own composter, making sure to check that the work is carried out correctly and safely.
The trainer collects all the material needed for creating a small composter at the center of the room or in a place where participants can watch, interact and participate to the activity easily.
The trainer starts drilling small holes in the side of the garbage bin, about 10 cm apart from each other creating a pattern of straight lines like in the picture. If you don’t have an electric drill, use a hammer and nail to hammer in holes at regular intervals. The holes are very important as they will provide passive aeration for the composting material.
The trainer can let the participants complete this task, making sure that they are using the drill in the safest way possible. When the group is quite big, the trainer can divide the participants in smaller groups (ideal size up to 7 people per group) and provide each group with a garbage bin.
A bigger hole can be drilled at the bottom of the bin, about 1 to 5 cm above the ground on the side. This bigger hole can be used to collect the compost tea that will most likely leak out of the bin, which is full of nutrients for nourishing the plants. A tap can be placed on this hole, like in the picture below, alternatively the hole can be left open (this will provide extra aeration, but will most likely dry most of the compost tea).
The bottom of the bin will then be filled with a layer of branches mixed with cardboard, paper and/or dry leaves. This bottom layer will help dry the compost draining the extra moisture present in the bin  preventing bad smells.
Now the compost bin is ready to be used.

The following information sheet helps you understand what to throw in your compost bin in order to ensure the best result.

GREEN“Greens” are the nitrogen-rich additions to your compost pile. These tend to have lots of moisture, break down quickly, and provide a quick burst of heat to your pile. While we call them “greens,” technically any plant matter will work here: coffee grounds, for example, are brown in color, but they’re rich in nitrogen, hence, they’re a “green.” BROWN“Browns” are the carbon-rich materials in your compost that add aeration to the pile and structure to your compost. They break down more slowly, so it’s a good idea to chop them fairly small if you’re able to.
  • Fruit and vegetable peels (thick peel like citrus, melon, watermelon … works too)
  • Broccoli stalks (or cabbage, etc …)
  • Coffee grounds (with moderation)
  • Tea leaves/tea bags (with moderation)
  • Old vegetables
  • Egg shells​
  • Cooked plain rice
  • Cooked plain pasta
  • Stale bread
  • Corn husks
  • Corn cobs
  • Old, less flavorful packaged herbs and spices
  • Seaweed
  • Houseplant trimmings
  •  Fresh leaves
  • Deadheads from flowers
  • Dead plants (not diseased)
  • Shredded newspaper
  • Shredded office paper/school papers
  • Shredded, non-glossy junk mail
  • Cardboard boxes (not with glossy coatings)
  • Straw
  • Fallen leaves
  • Chopped up twigs and small branches
  • Nut shells (avoid walnut shells as they can inhibit plant growth)
  • Sawdust (only from untreated wood)
  • Toilet paper, paper towel, or wrapping paper – tubes (cardboard)
  • Paper coffee filters (used)
  • Pressed paper egg cartons, torn into small pieces