Composting With Worms

 This section is probably of most interest to yardeners with kids five to ten years old.  I’m going to talk about worms; red wiggly squirmy worms.  I just set up my second worm composting system.  Called “The Worm Factory”, it is a very well designed worm composting device that works outside and inside the home; usually outside during the summer and inside during the winter.

The technical term for this activity is vermicomposting, but when you are a seven year old kid, it’s a box of worms, his or her worms.  Years ago I had a worm farm called the “Can O Worms” (    )  originally invented in New Zealand.  I produced worm castings ( a nice way to describe worm poop) for about five years.  When the son went to high school, worm farming was not cool so the worm farm was replaced by some other crazy idea.

I am trying the Worm Factory because it has many improvements to the design features of the Can O Worms, perhaps the most important being that it is odorless.  We kept the Can O Worms in the basement because sometimes it did smell a little bit, but I’ve got my Worm Factory in the pantry beside the kitchen; very convenient.

The primary reason to have a worm farm, besides being a fun project for kids,  is to recycle kitchen waste making incredibly valuable compost that when spread on the garden or mixed in with potting soil for container plants good things happen to those plants. It does magic, just like any quality compost.  Worm farming even fits into the Green Revolution that is becoming so popular.

 

The farm has stackable trays about 16 inches square and 4 inches deep.  Working one tray at a time, you add “bedding” material such as shredded newspaper, peat moss, chopped leaves or the like.  The bedding material acts as a home for the worms and eventually they will consume it along with the food scraps you add each day or two.  Usually you start with a pound of red worms which are attractive for this job because they reproduce so fast.  A pound of red worms has from 1000 to 2000 worms.  Their population expands every month according to how much food (scraps) you give them.  As they fill one tray with castings, you add trays.  At the end of one year you may be host to over 30,000 worms and they don’t make a sound.

Moisture is produced in the process of turning scraps into compost.  That liquid is caught at the bottom of the farm and can be removed using a handy spigot.  Compost tea, as it is called, is a wonderful tonic for houseplants and container plants any time of the year.

We refer to our worms as “our girls” but we have not yet tried to name each worm.

 

Worm Composting

 

            Worms are wonderful composters.  Various kinds of earthworms will find their way into any compost pile that is in contact with the bare soil.  They work their way around the outside layers of the pile, chomping and processing organic materials as they go.  Their castings are stuff of legend.  In a passive pile of leaves that is never turned, the worms will do as much work as the microorganisms in the year to two years it takes to turn that pile into compost.  When sheet composting is used or when leaves are used as mulch, it is earthworms which do much of the work of breaking down organic material and getting it into the soil. 

 

            Use worms as composting tools.  Purposely add worms to a pile outdoors, or set up a worm composting box in the basement to handle kitchen waste in the winter.  It is important to distinguish between the common earthworm (®MDUL¯Lumbricus terrestris®MDNM¯) which is resident in the yard year round and the composting worm or red worm®MDUL¯ (Lumbricus rubellus)®MDNM¯ which is highly specialized for composting duty but can not survive elsewhere.  Earthworms are attractive in the compost pile because they process lots of waste and then when the finished compost is spread around the yard, they go back into the soil and continue to contribute to soil quality as they go through their life cycle.  There are all kinds of varieties of worms that we all call "earthworms".  The nightcrawler is perhaps one of the most common of these "earthworms". 

 

[Photo - Earthworms in the compost pile]

 

            Earthworms perform valuable services in the compost pile.  One thousand earthworms in a compost pile will produce 35 pounds of nitrogen rich fertilizer during one gardening year.  The more earthworms resident in a compost pile, the richer the final compost in terms of nutrients used by the plants. 

 

            Earthworms make other very significant contributions to a compost pile and to garden soil as well. They secrete calcium carbonate, a compound that helps to moderate soil pH.  Earthworms can help change acid or alkaline compost materials toward a neutral pH over time.  As they move about a compost pile earthworms rearrange and loosen the compost materials, enhancing aeration and allowing more oxygen to penetrate the pile. Finally, by their tunneling, earthworms create access deeper into the  compost pile for countless smaller organisms, such as sow bugs and millipedes, that contribute to the decomposition process. 

 

[Photo - Showing earthworms next to composting worms for identification]

 

            Composting worms perform almost all the same functions in a compost pile, but there are some disadvantages that accompany the advantages of using them.  Known variously as red worms, composting worms, red wigglers, manure worms, or red hybrids, these worms reproduce very rapidly, much more rapidly than the common earthworm.  Consequently, they process more organic material than earthworms because they increase their population exponentially faster.  It takes just 8 red worms to produce 1500 new red worms in only six months. 

 

            Compost worms do not usually survive in the home landscape, so they must be purchased each season.  There are two types sold: ®MDUL¯Eisenia foetida®MDNM¯ can not live in the soil at all; ®MDUL¯Lumbricus rubellus®MDNM¯ can sometimes survive in the soil.  Both are good composting worms.  A pound of red worms (about 1000 to 2000 worms) typically cost between $10 and $12 from mailorder sources. (See list in resources section)

 

            Using Worms In The Compost Pile

            For obvious reasons, worms are not practical in compost piles that are run through any type of shredder.  The worms will not survive the process.  Worms are appropriate to help speed up decomposition in any pile that is turned from time to time.  They are most valuable in passive compost piles that are established and just left alone to rot.  Worms or any type will cut the decomposition time of a passive pile at least in half. 

 

[Photo - Adding worms to pile]

 

            Red worms are much more efficient than common earthworms, however they do require some attention if you wish to keep them alive once the pile is thoroughly decomposed and they have nothing to eat.  One pound of red worms added to a compost pile in the late spring will be sufficient to make a very noticeable difference in the speed of decomposition within the pile.  Unfortunately, composting worms are so voracious and efficient they often literally eat themselves out of house and home.  Once they digest most of the organic material in the pile, they are in danger of starving  to death.  To keep them going and to continue to reap the benefit of your investment, be sure to transfer them to a fresh pile of yard waste promptly.  

 

            Another concern is that, unlike earthworms, composting worms usually die if left in the pile over the winter in the North.  While earthworms just burrow down into the soil and hibernate until spring comes, red worms are exposed to the temperatures above the soil.  If you want to keep red worms going it will be necessary to devise a holding box for them in the basement, garage, or attic where temperature stay above freezing.  See discussion in the next section. 

 

            Vermicomposting With Worms In A Box

 

            Common earthworms are very difficult to raise in a box or "worm farm" in the home, advertisements in certain periodicals notwithstanding.  It is the composting worm or red worm that is best suited to life in a box in the basement.  Some homeowners use "vermicomposting"--composting with worms--all year long to process all the family's kitchen scraps, including meat scraps.  Other composters simply use the worm box to hold a proportion of their red worm population over the winter so they can be a nucleus for a new population in the outdoor compost pile in the spring.  Either way, the techniques are similar.

 

[Line drawing  - Showing box system]

 

            Red worms prefer a temperature range of from 55ø to about 85ø.  So the basement, a heated garage or attic, or a heated sun room are likely sites for the worm farm.  A properly managed worm box will not smell or attract insects.  However, if things get a bit out of balance, some fruit flies might appear or some odor might develop.  Once the box is brought back into balance those problems disappear, but the potential for those problems probably will keep the worm box out of the living room. 

 

            The first issue is the size and shape of the worm box.  In Chapter ### there are several detailed designs for worm boxes.  Its size will depend upon how much garbage you intend to process.  The rule of thumb is roughly 1 square foot of surface area for the number of pounds of garbage produced per week; 7 pounds per week needs about 7 square feet of surface area or a box about 2 feet by 3.5 feet in area.  The container should be from 8 to 12 inches deep, not much deeper, to avoid compaction. Construction details and materials lists are found in Chapter ###.

 

            The number of worms in the box will control how much garbage you can process.  About 2000 composting worms (2 lbs.) can process 7 pounds of kitchen garbage in a week.  That ratio of 2 lbs of worms for every pound of garbage disposed of each day is a standard way to calculate how many worms you need and how big a worm is necessary.  If about 1/2 pound of kitchen waste a day is discarded, then 1 pound of worms should be sufficient to do the job.  Remember, red worms will multiply quite quickly to cover any increase in garbage intake. 

 

[Photo - Showing bedding material in worm box]

 

            Worms live in some kind of bedding material.  It must be some kind organic materials such as chopped leaves, shredded newspaper, shredded cardboard, or peat moss.  Add a few handfuls of garden soil to the bedding mix to introduce microbial decomposers to the process.  The two main concerns are density and moisture.  As it decomposes along with the garbage, the organic bedding material will get more dense over time reducing oxygen access for the worms.  It may be necessary to add bedding material part way through the winter to assure that the worms enjoy sufficient oxygen to promote their activity and reproduction. 

 

            Composting worms also need a fairly moist environment to survive.  The standard is about 75% moisture.  Determine that  amount of moisture by weighing the bedding material and then mixing it with water equal to three times that weight.  One pint of water weighs one pound.  If you have 4 pounds of bedding material, then 12 pounds of water will be 12 pints or 3 gallons.  The bedding material should be completely and thoroughly moistened before the worms are introduced.  Most worm farmers cover the worm box with a sheet of black plastic or a wooden cover to keep in the moisture and keep out the light. 

 

[Photo - showing adding garbage to worm box]

 

            As soon as the worms are established in their home, garbage can be introduced to the box.  The best way is to add the garbage in some kind of pattern so that once some material has been added to a particular spot, that spot is not disturbed with any new garbage at least for a few weeks, ideally for a month.  Garbage does not have to be chopped up, but if it is, it will break down much more quickly.  Some homeowners put their garbage in a blender and chop it finely and, after draining the liquid, add the chopped material to the worm farm.  It will be compost in just a few weeks.  When the garbage is added, in any form, be sure it is covered with bedding material. 

 

            Worm boxes need some renewal in two to four months.  There are several techniques for adding new bedding while removing some or all of the finished compost.  The easiest method is to take one half of the material in the box, including the worms, and spread it out in the landscape as compost.  The worms will die and add fertilizer to the compost.  The space made available by this procedure is filled with fresh bedding material.  If no new garbage is added to the old bedding material, the worms will migrate into the new bedding material in 3 to 4 weeks.  Then you can remove the other half of the old material, including any worms that might be lagging behind, and replace it with new bedding.  The worm farm is now good for another two or three months. 

 

[Photo - Showing the removal of part of the compost in a worm box]

 

            In the spring, move the worm box outside to a shady area or simply dump the worms onto the compost pile.  Next fall set it up again in the basement and allow the red worms to handle the kitchen garbage load for another winter. 

 

Composting With Animals

 

            Raising rabbits and chickens in small numbers for food or as pets is popular all across the country, usually, though not exclusively, in rural areas.  A major problem associated with raising small stock such as this in suburban areas is the danger of noxious odors which offend neighbor's.  To both solve the odor problem and improve a composting operation combine the two activities.  Building the rabbit hutch or small chicken coop directly over the compost bin, simultaneously eliminates the possibility of manure odors and increases the value of the compost.  Look in Chapter ### for detailed plans for building a rabbit hutch/compost bin combination.  A similar structure can be built for a small number of chickens. 

 

[Line drawing or Photo - Showing rabbit hutch over compost bin]

 

            In this arrangement, the manure from the animals falls into the compost through chicken wire flooring in the hutch or coop.  The manure is very quickly attacked and processed by the macro and micro life in the top surface layer of the compost pile.  In these circumstance it is wise to turn the pile about once a month to prevent the build up of a concentration of manure on the top of the pile which might exceed the ability of the microbial population's to process the stuff.  The final compost from such an arrangement is going to have a very high nutrient value and can be used as a complete fertilizer substitute in any part of the yard or garden. 

 

 

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