Why Compost With Worms?
In a nutshell, worm compost is made in a container filled with moistened bedding
and redworms. Add your food waste for a period of time, and the worms and micro-organisms
will eventually convert the entire contents into rich compost.
What Do I Need To Get Started?
- Container
We use wood and plastic containers. Either build or buy, or use your imagination
and recycle something like an old dresser drawer, trunk, or discarded barrel.
We prefer wood because it is more absorbent and a better insulator for the worms.
We use plastic containers but find that the compost tends to get quite wet. Experiment
and find out what works for you and your worms.
Guide To Size Of Container
In
Worms Eat My Garbage, Mary Appelhof suggests weighing your household food waste
for one week (in pounds), and then provide one square foot of surface area per
pound. The container depth should be between eight and twelve inches. Options
to one large (and heavy) box are a number of smaller containers for easier lifting
and moving and more choice of location. The book illustrates a variety of containers.
Depending on the size of the container, drill 8 to 12 holes (1/4 - l/2 inches)
in the bottom for aeration and drainage. A plastic bin may need more drainage
- if contents get too wet, drill more holes. Raise the bin on bricks or wooden
blocks, and place a tray underneath to capture excess liquid which can be used
as liquid plant fertilizer.
The bin needs a cover to conserve moisture and provide
darkness for the worms. If the bin is indoors, a sheet of dark plastic or burlap
sacking placed loosely on top of the bedding is sufficient as a cover. For outdoor
bins, a solid lid is preferable, to keep out unwanted scavengers and rain. Like
us, worms need air to live, so be sure to have your bin sufficiently ventilated.
- Bedding
It is necessary to provide a damp bedding for the worms to live in, and to bury
food waste in.
Suitable bedding materials are shredded newspaper and cardboard,
shredded fall leaves, chopped up straw and other dead plants, seaweed, sawdust,
compost and aged manure. Try to vary the bedding in the bin as much as possible,
to provide more nutrients for the worms, and to create a richer compost. Add
a couple of handfuls of sand or soil to provide necessary grit for the worm's
digestion of food.
It is very important to moisten the dry bedding materials
before putting them in the bin, so that the overall moisture level is like a
wrung-out sponge. The bin should be about three-quarters full of moistened bedding.
Lift the bedding gently to create air spaces which help to control odours, and
give freer movement to the worms.
- Worms
The two types of earthworm best suited to worm composting are the redworms: Eisenia
foetida (commonly known as red wiggler, brandling, or manure worm) and Lumbricus
rubellus They are often found in aged manure and compost heaps. Please do not
use dew-worms (large size worms found in soil and compost) as they are not likely
to survive.
Where To Get Your Worms?
If you feel adventurous, find a horse stable or farmer with a manure pile
and collect a bagful of manure with worms. Check your own or a friend's compost
bin for worms. You can also purchase worms. Call the Compost Hotline for more
details on local (British Columbia) sources of redworms.
How Many Worms Do I Need?
Mary Appelhof suggests that the correct ratio of worms to food waste should
be: for one pound per day of food waste, use two pounds of worms (roughly 2000).
If you are unable to get this many worms to start with, reduce the amount of
food waste accordingly while the population steadily increases.
What Do I Feed My Worms?
You can compost food scraps such as fruit and vegetable peels, pulverized
egg shells, tea bags and coffee grounds. It is advisable not to compost meats,
dairy products, oily foods, and grains because of problems with smells, flies,
and rodents. No glass. plastic or tin foil, please.
To avoid fly and smell problems,
always bury the food waste by pulling aside some of the bedding, dumping the
waste, and then cover it up with the bedding again. Bury successive loads in
different locations in the bin.
Where Should I Locate My Worm Bin?
Worm bins can be used indoors all year round, and outdoors during the milder
months. The advantage of mobile bins is that they can be moved when weather conditions
change. Indoors, basements are excellent locations (warm, dark and dry), but
any spare space can be utilized, so long as temperatures are between 40-80 degrees
F. We know dedicated worm composters who have convenient kitchen counter worm
bins. Outdoors, bins can be kept in sheds and garages, on patios and balconies,
or in the yard. They should be kept out of hot sun and heavy rain. If temperatures
drop below 40 degrees F., bins should either be moved indoors, or well insulated
outdoors.
How Do I Maintain My Bin?
If you have the correct ratio of surface area to worms to food scraps, there
is little to do, other than adding food, until about two and a half months have
passed. By then, there should be little or no original bedding visible in the
bin, and the contents will be brown and earthy looking worm castings. The contents
will have substantially decreased in bulk too.
It is important to separate the
worms from the finished compost, otherwise the worms will begin to die. There
are several ways to do this. and you can discover which is best for you. The
quickest is to simply move the finished compost over to one side of the bin,
place new bedding in the space created, and put food waste in the new bedding.
The worms will gradually move over and the finished compost can be skimmed off
as needed.
If you have the time or want to use all the compost, you can dump
the entire contents of the bin onto a large plastic sheet and separate the worms
manually. Most children love to help with this process and you can turn it into
a fun lesson about worms for them. Watch out for the tiny. lemon-shaped worm
cocoons which contain between two and twenty baby worms! By separating the worms
from the compost, you save more worms for your next bin. Mix a little of the
finished compost in with the new bedding of the next bin, and store the rest
in plastic bags for use as required.
Where Do I Use My Compost?
The compost can be mixed with potting soil and used for houseplants and patio
containers. It is an excellent mulch (spread in a layer on top of the soil) for
potted plants. If it is screened, it can be added for potting mixes for seedlings,
and finely sprinkled on a lawn as a conditioner. lt can be used directly in the
garden, either dug into the soil or used as a mulch.
Common Problems & Solutions
The most common problem is unpleasant, strong odours which are caused by lack
of oxygen in the compost due to overloading with food waste so that the food
sits around too long, and the bin contents become too wet. The solution is to
stop adding food waste until the worms and micro-organisms have broken down what
food is in there, and to gently stir up the entire contents to allow more air
in. Check the drainage holes to make sure they are not blocked. Drill more holes
if necessary. Worms will drown if their surroundings become too wet.
Worms have
been known to crawl out of the bedding and onto the sides and lid if conditions
are wrong for them. If the moisture level seems alright, the bedding may be too
acidic. This can happen if you add a lot of citrus peels and other acidic foods.
Adjust by adding a little garden lime and cutting down on acidic wastes.
Fruit
flies can be an occasional nuisance. Discourage them by always burying the food
waste and not overloading. Keep a plastic sheet or piece of old carpet or sacking
on the surface of the compost in the bin. If flies are still persistent, move
the bin to a location where flies will not be bothersome. A few friendly spiders
nearby will help control fly problems!
The Final Word
Taking worms out of their natural environment and placing them in containers
creates a human responsibility. They are living creatures with their own unique
needs, so it is important to create and maintain a healthy habitat for them to
do their work. If you supply the right ingredients and care, your worms will
thrive and make compost for you. Happy and successful composting!
www.nyworms.com/vermicomposting.htm
www.ciwmb.ca.gov/Organics/Worms/
www.wormwoman.com/acatalog/vermicomposting.html
www.cityfarmer.org/wormcomp61.html
OCRRA's compost
bin options
