waste Icon

6 COMPOST FOOD SCRAPS VIA WORM BIN

This action focuses on eliminating the food-scrap waste stream by turning this material into nutrients using a worm bin.

  • Spring Icon
  • Summer Icon
  • Autumn Icon
  • Winter Icon

why?

compost-food-scraps-via-worm-bin Pie ChartComposting food waste has a myriad of environmental benefits such as improving soil health and structure, increasing drought resistance as well as reducing and even eliminating the need for supplemental water, fertilizers and pesticides (EPA). Since the beginning, humans have been finding ways to facilitate this process. Even nomadic cultures did this (somewhat unknowingly) as they tended to leave organic wastes behind as they moved, restoring nutrients to the soil and the surrounding environment. Modern societies, however, simply want to get rid of waste as quickly as possible, leading to the massive amount of waste in accumulated in landfills each year. The potential nutrients in organic waste are lost when disposed of in landfills. Here, they can't be used to build up the nutrients in soil, and instead turn into a sludge under anaerobic conditions.

Man-made, synthetic materials cannot be digested by the earth the way natural materials can.

Because of the complications of reusing synthetic materials, it is essential that we find ways to put our organic "waste" to good use.

While 64.7% of yard trimmings are composted, the remaining percentage of potentially compostable materials is typically land-filled. Cities such as Seattle and San Francisco have mandatory composting laws, but most municipalities do not have a system of composting set in place at this point. According to the EPA's Municipal Solid Waste in the United States 2007 Facts and Figures: "Over eight percent of the waste that each person generates each day could be recovered for composting. That works out to over 140 pounds per person, per year".

While plastic may be the most difficult type of waste to deal with in the long term, it certainly is not the only material which causes environmental damage. According to the EPA, Americans throw away more than 25 percent of the foods we prepare, about 96 billion pounds of food waste each year. This includes uneaten food and food preparation scraps.

There are several misconceptions about composting which are barriers to understanding the importance of this natural process, and the ease with which we could incorporate it into our lives:

COMMON MISCONCEPTION #1

It doesn't matter if you compost because organics will just decompose in the landfill.

Because landfills are so tightly packed with matter, they become anaerobic environments, turning any organic matter into sludge at best, or simply preventing decomposition entirely. Because of this, a banana peel that gets thrown away might as well be a milk jug because it isn't going anywhere. On top of this, the decomposition of food and other organic waste materials under anaerobic (without oxygen) conditions in landfills produces methane, a greenhouse gas twenty-one times more potent than carbon dioxide. When composting, on the other hand, aerobic bacteria manage the chemical process by converting the inputs into heat, carbon dioxide and ammonium. The ammonium is further refined by bacteria into plant-nourishing nitrites and nitrates.

COMMON MISCONCEPTION #2

Compost will accumulate and you will have no where to put it!

Worms in a worm composting bin have the ability to moderate their population to eat as much waste as added during a given period of time, keeping the compost from accumulating. More food=more worms; less food=less worms. The compost becomes a dense, nutrient-rich mixture which is perfect organic fertilizer for indoor plants or to use in a backyard garden in the spring.


how to do this action:

food composting imagesA worm composting bin can be made simply and inexpensively with two large rubber tubs, a light-colored sheet, and a bungee cord. The rubber tubs should be slightly different depths so that when stacked inside of each other there is an air space of a few inches. The tub on top should have holes drilled into the bottom so any liquids drain into the lower bin to reduce sludge buildup. While worms are excellent for digesting our food, they are not the most intelligent creatures. They are aware of at least two things, however: (1) Eating anything in their path, and (2) Avoiding light sources. As many people have learned the hard way, if worms are unable to identify where a light source is coming from, they will crawl freely in the worm bin and eventually make their way outside onto your kitchen floor! This is why it is important to cover the bin with a translucent material of some kind (we recommend a light sheet). Because the bin should not smell bad (if it does, something is wrong), the sheet will be enough of a barrier to keep this under control. With light coming in from the top of the bin, the worms will avoid crawling up the walls and escaping. Still, the bin remainsdark enough that the worms are comfortable coming to the top of the soil.

Red Wrigger composting worms can be purchased at many gardening centers or you can introduce a small tub-full of someone else's worms to start your worm population. The worm population will quickly grow based on how much food is available. It is easier to start with some organic matter (dirt) already in the bin as well as a bed of damp newspaper shredding. Avoid putting too much food in the bin at first, until a small amount of dark brown compost has been created.

As for food scraps, worms will eat just about anything. However, for faster composting it is recommended to cut up food scraps to at least 1" pieces or smaller. Cutting up pieces allows new food to mix with already existing compost to avoid any rotting (and smells) of food as well. When adding food scraps, dig a hole into the compost, place all cut up food scraps in the bin and cover the hole completely with compost. It is important to make sure that all food scraps are buried under a little bit of finished compost to avoid bugs being attracted to the bin and breeding inside it. Create a cycle of digging holes in different areas of the bin each day so that by the time you arrive at the initial hole, the material inside has been composted enough to add more.

Many kinds of foods can be added to a worm bin. It is not recommended that meat products of any kind are used, as worms cannot digest meat and bacteria will accumulate in the bin. Bio-plastic 'Compostable' products such as cups, spoons and plates are also not ideal for worm bin composting as the decomposition within the bin does not produce enough heat to compost these products.

There shouldn't be any problems with fruit flies (or other bugs) if the food scraps are completely covered in the compost bin. However, flies may be attracted to a kitchen composter. Many people use small counter-top kitchen composters to store food scraps before dumping them. If flies become attracted to a counter-top scrap storage, it is recommended that you place the food scraps into the worm bin immediately to avoid letting them collect and attract flies.

After about three months of composting the mixture will be decomposed enough -or 'finished'-to be safe to use. It can be used to make compost tea (a natural fertilizer for garden or indoor plants) or simply spread on a garden, returning nutrients to the soil from where they originally were taken. A way to harvest the mixture is to move the compost to one side of the bin. On the other side, place a new wet bedding of newspaper and some new food scraps. The worms will eventually begin to migrate to the new food scraps on the other side (Campbell), leaving the finished compost ready for use.

For more information about starting and maintaining a worm composting bin, check out the book, 'Worms Eat my Garbage' by Mary Applehof.


what will be measured?

KEY QUESTIONS

QUANTITATIVE QUESTION: How many pounds of waste were you able to divert from the waste stream by composting organic waste (food scraps)?

QUALITATIVE QUESTION: How does the experience of composting food scraps via a worm bin affect your happiness, convenience, health and costs?

BASELINE WEEK TRACKING

QUANTITATIVE
During the baseline tracking week before the project begins, use the corresponding spreadsheet (WST6_BASELINE) to track item by item all organic waste that you create, and collect this waste in a separate ‘organics’ bin.

QUALITATIVE


Qualitative Scale

Using the above scale as a visual, rate each of the following criteria on the spreadsheet (WST6_BASELINE) as it relates to your current waste habits:

  • 1. SATISFACTION/HAPPINESS
    (Overall, how much enjoyment or dissatisfaction do you get out of doing and completing this behavior?)

  • 2. CONVENIENCE
    (How easy/difficult and accessible/inaccessible is this behavior for you to do and complete?)

  • 3. HEALTH
    (How healthy/unhealthy and safe/unsafe does this behavior make you feel?)

  • 4. COST
    (How much does this behavior cost? Use positive numbers for being above average and negative numbers for being below average and zero for being average.)

IMPLEMENTATION PHASE TRACKING

QUANTITATIVE
Use the corresponding spreadsheet (WST5_QUANTITATIVE) to track all organic waste items that you were unable to compost and why.

QUALITATIVE
Part 1 - Ranking


Qualitative Scale

Using the above scale as a visual, rate each of the following criteria individually each week on the spreadsheet (WST6_QUALITATIVE). Your answers should not be rated in comparison to your baseline week, but in general as a reflection of how you are feeling.

  • 1. SATISFACTION/HAPPINESS
    (Overall, how much enjoyment or dissatisfaction do you get out of doing and completing this behavior?)

  • 2. CONVENIENCE
    (How easy/difficult and accessible/inaccessible is this behavior for you to do and complete?)

  • 3. HEALTH
    (How healthy/unhealthy and safe/unsafe does this behavior make you feel?)

  • 4. COST
    (How much does this behavior cost? Use positive numbers for being above average and negative numbers for being below average and zero for being average.)

Part 2 - Blogging
Keep a narrative log of your experiences as you implement this action and how it has affected your life. Some of the following questions might be helpful as you reflect upon your experiences.

What was most challenging about this action? Why? How the worm bin was constructed and started? Any problems with starting the compost process? How often food is added to the bin? What kind of food is most often added (produce, leftovers...)? Any problems, concerns or tips for future composters? What tools would have helped you complete this action more fully (more correctly or more of the time)? Were their other side benefits to this action in comparison to how you normally dispose of trash and waste?


resources

'Worms Eat My Garbage' by Mary Applehof

ACTION SPREADSHEETS

The spreadsheets referred to above can be found in the Excel file at the following link:

WST6_Compost All Organic Waste Via Worm Bin Spreadsheet

If you prefer to enter your responses by hand, printable PDFs of each spreadsheet can be found at the following links (at the end of the project, all data will have to be entered into the Excel spreadsheet):

WST6_BASELINE
WST6_QUANTITATIVE
WST6_QUALITATIVE