Home - Organic and Natural Products

Home - Home Garden - Waste Reduction at Home

Home Composting for Waste Reduction at Home

How to use home waste to create an organic garden at home.

Home Gardening - Use Worms to make VermiCompost - Home Project -

Worm composting (or vermicomposting) is a natural and efficient way to recycle your organic kitchen scraps. And it sure beats plowing through knee-high snowdrifts to the compost pile in the middle of winter! Worm bins really require very little in the way of maintenance and care. You can keep them anywhere the temperature will not go down to freezing such as a basement, insulated garage or under the kitchen sink. The best temperature range is 55-77 Fahrenheit.
This is a great project to do with kids; it's easy to make compost using worms as long as you have the right container, bedding material and the right worms. And the finished product, consisting mostly of worm castings, can be used with perlite to make a houseplant potting mix, added to planting holes when transplanting seedlings, or simply incorporated into flower or vegetable beds.

Kitchen waste

Greens - If too much kitchen waste is added for the worms to process, the waste will putrify. A balance between "green matter" such as kitchen scraps and "brown matter" such as shredded newspaper for bedding must be maintained in order for the worms to do their work (this is often referred to as the carbon to nitrogen ratio). This balance should be approximately one part "green matter" for every two parts "brown matter". Covering the kitchen scraps with a layer of "brown matter" has the added benefit of reducing odor and insect problems. Avoid grass clippings or other plant products that have been sprayed with pesticides. In a small bin, this includes banana peels which can kill everything in the bin, if heavily sprayed.

Any non-biodegradable materials don't belong in a worm box.

Meats - Although proteins such as fats and meat scraps can be processed by a vermicompost bin, doing so tends to attract scavengers and should be avoided if this is a risk. Worms are unable to break down bone or synthetic material.

Over the long term, care should be taken to maintain optimum moisture levels and pH balance. In a non-continuous-flow vermicomposting bin, excess liquid can be drained via a tap and used as plant food. A continuous flow bin will not retain excess liquid and requires extra water to be added to keep the bedding moist. It is commonly believed that too many citrus peels in the material to be composted can cause an intolerable level of acidity, which can be mitigated by adding an occasional handful of lime. It is more likely to be the chemical d-limonene (best known for being the juice that spurts out when an orange is peeled) which affects worms.

As worms breathe through their skin, it is not a good idea to add too much fat/oil to the bin, as it can hinder their breathing ability. Other foods it is not recommended to feed too often are onions, garlic, tea leaves/tea bags, coffee grounds, and heavily salted foods. These are all reputed to have an adverse effect on the pH in the bin, which should be neutral or slightly alkaline.

Worms as well as other microorganisms in the composting process require oxygen, so the bin must "breathe". This can be accomplished by regularly removing the composted material, adding holes to a composting bin, or using a continuous-flow bin. If insufficient oxygen is available, the compost will become anaerobic. This will provide a host environment for a different type of decay process which produces a strong odor offensive to most people. Thistype of decay is found in swamps and bogs and is responsible for the stench sometimes found in these environments.

Sompe people don't use meat or milk products in the worm bin. Mice and rats could be attracted to the odors!

Cat litter should not be used - . The odor of cat urine is intolerable to worms, plus the ammonia in the urine could kill the worms! Cats can carry the disease Taxoplasma gondiii that can be transfered to humans and cause birth defects.

You can either make your worm bin yourself or order it from a number of different sources. Common materials for a do-it-yourself project are opaque plastic storage boxes and wooden boxes built from exterior-grade plywood. A basic design would be 1 foot high, 2 feet deep and 3 feet wide with aeration holes in the bottom. Depending on the size of your container, you'll need to drill 8 to 12 holes (1/4-1/2 inch in size) in the bottom. A simple cover can be made from a sheet of black plastic. A cover will help conserve moisture and provide darkness for the worms. A box this size will accommodate about 6 pounds of kitchen scraps a week (the average amount from a family of 4-6). You will need to keep the bin elevated at least an inch off the ground for air circulation. Place a tray underneath to capture excess liquid which can be used as liquid plant fertilizer.

The bottom of your bin will need to be lined with a 2 to 3 inch layer of bedding material. Cellulose-based materials like shredded newspaper, corrugated cardboard or coarse sawdust are best. Tear newspaper or corrugated cardboard into 1 to 2 inch-wide strips. Before putting bedding material into the bin, dampen it with lukewarm water until it has the same moisture content as a wrung-out sponge. Adding a little garden soil or leaf mold to the bedding will provide microorganisms for the composting process and grit for the worms' gizzards. Check your bedding at least once a week to make sure it stays damp. Add water if necessary by misting with a spray bottle.

After spreading the bedding over the bottom of the bin, you're ready to add worms! What worms do you buy? Of the 17 species available in North America, you want redworms or red wrigglers. You can buy them at a bait shop or through mail order. You want redworms because they can process large amounts of kitchen scraps, don't mind confined spaces, reproduce well in culture and tolerate a wide range of temperatures. For the bin described above, you'll need about 2 pounds (about $25-$35). You'll get between 600 and 1,200 worms per pound. They will be red and from 2 to 4 inches long. Put your worms on top of the bedding and watch them quickly burrow to escape light.

Now comes the fun part, feeding your worms. Put leftover kitchen scraps into the bin: vegetables, fruit rinds and peelings are great. Bread, coffee grounds, cereal, crushed eggshells, pasta or rice and houseplant clippings are also okay. Food should be cut into small pieces and buried in the bedding every few days. By covering food waste with a few inches of bedding, you avoid odors and pests (like fruit flies). Rotating the burial places in the bin will provide your worms with a balanced diet of kitchen scraps and bedding. As with outdoor compost, you want to stay away from meat, bones, oils and dairy products.

After 6 or 8 weeks of feeding the worms, most of the bedding should be gone and a dark, crumbly soil-looking material should be in its place. Now it's time to harvest. Do this by pushing the nearly finished compost to one side of the bin. Put fresh moistened bedding with some fresh garbage in the vacant side. Over the next few weeks the worms will migrate to the new bedding, and you can harvest. Take the finished compost out, and put fresh bedding in, starting the cycle all over again.

On occasion, unpleasant odors may waft from your bin when it is overloaded with food waste. If this occurs, gently stir up the entire contents to allow more air in. Stop adding food waste until the worms and micro-organisms have broken down what is in the bin. If that doesn't solve the problem, check the drainage holes to make sure they are not blocked. Drill more holes if you need to. If the moisture level seems right, the bedding may be too acidic due to a lot of citrus peels and other acidic foods. Adjust by adding a little lime and cutting down on acidic wastes.

Discourage fruit flies by always burying food scraps and not overloading the bin. If flies persist, move the bin to a location where the flies will not be bothersome.