How to Start a Vermicomposting Bin

    The materials needed to start a vermicomposting system are simple and inexpensive. All you will need are:

    •  a worm bin,
    •  bedding,
    •  water,
    •  worms, and
    •  your food scraps.

    Worm Bin. A suitable bin can be constructed of untreated, non aromatic wood, or plastic container to be purchased (e.g. a Rubbermaid tub). A wooden box is better if you will keep the worms outdoors, because it will keep the worms cooler in the summer and warmer in the winter.

    If a plastic container is used, it should be thoroughly washed and rinsed before the worms and bedding are added. The bin size depends on the amount of food produced by your household. The general rule of thumb is one square foot of surface area for each pound of garbage generated per week.

    Redworms or Red Wigglers (the type used for vermicomposting) thrive in moist bedding in a bin with air holes on all sides but holes on the sides and bottom may not be practical for indoor storage. For aeration, drill a minimum of nine l/2-inch holes in the top (i.e., the lid) of your bin. For drainage, drill the same number of holes in the bottom of the bin.  Some people suggest a fine screen on the inside bottom of your bin to prevent worms and bedding from escaping. If you do drill holes in the bottom, place a plastic tray under the worm bin to collect any moisture that may seep out. Drilling holes on the upper sides of your bin will also help your worms get needed oxygen and prevent odors in your worm bin. Keep a lid on the bin, as worms like to work in the dark. You may remove the lid for a few days if your moisture levels increase too much. Store the worm bin where the temperature remains between 14° and 25°C.

      Bedding. The worms need bedding material in which to burrow and to bury the garbage. It should be a non toxic, fluffy material that holds moisture and allows air to circulate. My first choice in bedding is potting soil as it create lots of awesome compost, is a good odor trap, and does not need to be replenished until your batch is changed completely. Other suitable materials include shredded paper (such as black-and-white newspapers, paper bags, computer paper, or cardboard); composted animal manure (cow, horse, or rabbit); shredded, decaying leaves; peat moss (which increases moisture retention); or any combination of these. Do not use glossy paper or magazines. Add two handfuls of soil to supply roughage for the worms. Adding crushed eggshells provides not only roughage but also calcium for the worms, and it lowers acidity in the bin. About 4 to 6 pounds of bedding is needed for a 2- foot-by-2-foot bin (for two people), and 9 to 14 pounds of bedding should be used in a 2- foot-by-3-foot bin (for four to six people). Worms will eat man of these types of bedding, so you will need to add more within a few months.

    Water. The bedding must be kept moist to enable the worms to breathe. To keep bedding moist, add 1 liter of water for each 10-12 liters of bedding. If the top of the bedding dries out, use a plant mister to spray some water on it. If the worms are exiting the bedding and crawling up the sides of you container, it may be too wet. Leave the lid off your bin for a few days to dry out a bit.

    Worms . It is important to get the type of worms that will thrive in a worm bin. Only redworms or red wigglers which are "composting worms" should be used (do not use night crawlers or other types of worms).

    Food Scraps. Feed your worms any non-meat, non-dairy organic waste such as vegetables, fruits, eggshells, tea bags, coffee grounds, paper, coffee filters, and shredded garden waste. Worms especially like bananas, cantaloupe, watermelon, and pumpkin. Limit the amount of citrus fruits that you add to the bin to prevent it from becoming too acidic. Break or cut food scraps into small pieces so they break down easier. Do not add meat scraps or bones, fish, greasy or oily foods, fat, tobacco, or pet or human manure. Be sure to cover the food scraps completely with the bedding to discourage fruit flies and molds. One pound of worms will eat about four pounds of food scraps a week. If you add more food than your worms can handle, anaerobic conditions will set in and cause odor. This should dissipate shortly if you stop adding food for a while.

    Starting the Process

    To start your vermicomposting system, first select a location for your worm bin. Popular indoor spots are the kitchen, pantry, bathroom, mud room, laundry room, or basement. If you want to keep your worm bin outside, put it in the shade during the hot summer and shelter it from the cold in winter by placing it in a garage or carport, or putting hay bales around the bin to allow air to circulate around the bin, and keep it protected from flooding, because the worms can drown.

    Next, prepare the bedding. I fill my plastic bin ¾ full of potting soil and add enough water so that if you squeeze a handful of the soil, it sticks together but no water is squeezed out. If you want to use newspapers, fold a section in half and tear off long, half-inch to inch wide strips (go with the grain of the paper and it will tear neatly and easily). Soak the newspaper in water for a few minutes, then wring it out like a sponge and fluff it up as you add the newspaper to your worm bin. Aim for the bedding to be very damp, but not soaking wet (only two to three drops of water should come out when you squeeze the bedding material). Spread the bedding evenly until it fills about three-quarters of the bin. Sprinkle a couple of handfuls of soil (from outdoors or potting soil) into the bedding to introduce beneficial microorganisms and aid the worms' digestive process. Fluff up the bedding about once a week so the worms can get plenty of air and freedom of movement.

    Gently place your worms on top of the bedding. Leave the bin lid off for a while so the worms will burrow into the bedding, away from the light. The worms will not try to crawl out of the bin if there is light overhead. Once the worms have settled into their new home, add food scraps that you have been collecting in a leak-proof container. Dig a hole in the bedding (or pull the bedding aside), place the food scraps in the hole, and cover it with at least 10-15cm of bedding. After this first feeding, wait a week before adding more food. Leave your worms alone during this time to allow them to get used to their new surroundings. Bury food scraps in a different area of the bin each time. Worms may be fed any time of the day. Do not worry if you must leave for a few days, as the worms can be fed as seldom as once a week. Note: Do not be surprised to see other creatures in your worm bin, as they help break down the organic material. Most of the organisms will be too small to see, but you may spot white worms, springtails, pill bugs, molds, and mites.


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