INITIAL SETUP AND OPERATION
My bin is a 53 litre Roughneck tote with newspaper bedding but my worms (Eisenia fetida) came in peat moss / animal manure (pellets?) so the resulting bedding was a mixture. My organic waste is minimal so the tote is divided in half with a wire baking rack mounted vertically in the middle of the bin and only one half is used at a time. There are no drainage holes as the active end of the bin is elevated to allow water to drain to the idle side. A turkey baster is used to remove any accumulated leachate.
The bin was feed once a week using the pocket feed method for the first six weeks then I went on holidays. I set up an Automatic Plant Waterer from Lee Valley in the bin feeding from a four litre jug of rain water to keep the bedding moist. As it turned out I was away longer than planned in total about six weeks. During that time the waterer used about two litres and the bedding was almost completely turned into compost. The volume was reduced by about half.
I fed the bin in the compost when I got back and a week later filled the empty side with new bedding and fed the bin there. Shredded newspaper and corrugated cardboard were used for bedding this time. My original plan had been to use the "lateral migration" method of harvesting. However further researching on the web revealed that it can take months for all the worms to move into the new bedding. I also became worried about the reduced ventilation and drainage now that both sides of the bin were occupied.
Due to the above and a desire to see the what the compost looked like and how many worms had survived in my absence I became impatient. My curiosity won out and I decided to complete my first harvest using the pile and hand separate method. I began by removing the drier vermicompost from the top and sorting it in a plastic tub. Since I had fed the bin recently in the original bedding/compost a lot of worms were still present. I ended up hand sorting to separate out the worms and transfer them to the new bedding. It seemed like most of the larger worms had died off but there were plenty of small worms and cocoons in the compost. I continued removing layers of drier material from the top of the bin every day until it was empty.
There was a lot of unworked peat like material in the compost. Some of it may have been animal droppings as I purchased my worms from a wildlife farm. Once I had removed the worms, cocoons and any leftover large pieces of shredded paper I sieved the material through 1/4" screen. This produced about three kilograms of fairly dry vermicompost.
It was interesting experience to see all the worms and cocoons and I'd recommend to newbies to do it at least once but it is a lot of work.
I've modified my bin now with perforated pipes and vents on the lid like the Worm-a-way bins to provide aeration when both sides of my bin are full. To allow for drainage I also added a false bottom although there is no outlet for water from the bin. A turkey baster is used to remove any accumulated leachate.
I plan to use the lateral migration method for my next harvest and allow the worms a couple of months to move across before harvesting the compost. See "After 17 Weeks" below.
There are now further sections on "The Second Harvest" and "My Current Bin and Schedule" as it stands after three years of verimcomposting.
I also have some Canadian Vermiculture/Vermicomposting Links at the bottom of the page.
Photos
My modified bin on casters sitting in a corner of the kitchen along with a Kitchen Compost Pail. The pail cost more than the bin :o)
Top view of the interior of the bin showing the ventilation pipes, false bottom covered in landscape fabric and the wire baking rack separating the two halves of the bin
Shredded newspaper and cardboard bedding with castings and a couple of worms diving for darkness. The long white object (bottom left) is a sprout of some sort.
My harvester :o) The sieve sits nicely in the box which is lined with a plastic bag to catch the vermicompost. I use the same box for my paper shredder.
The vermicompost after sieving. It weighs about 3 kg and fills a box 25cm X 25cm X 18cm.
17 WEEKS LATER
During the fall of 2004 I fed the worms regularly every week. I'd estimate that the volume fed weekly was approximately one and a half litres. Kitchen scraps were supplemented with fallen leaves to keep the volume constant. I bought a spray bottle and misted the bin daily. Additional water was added when I thought the bedding needed it.
After 17 weeks the volume in the bid had fallen by about one third. New bedding (cardboard and newspaper) was added to the vacant side and the casting were piled up against the grate and new bedding. The slope of the floor of the bin was reversed so that any excess moisture will drain away from the new bedding to the bottom corner of the bin exposed by the piled castings.
My plan was to leave the castings in place for a couple of months to allow the worms plenty of time to migrate into the new bedding. All feeding and misting/watering will be done in the new bedding only. See "The Second Harvest" below
Top view of the interior of the bin after 17 weeks. The volume is reduced by about one third and is mostly comprised of dark castings.
New bedding added to the previously vacant side. The surface of the castings is several centimetres below the new bedding.
Castings are piled up against the grate and the new bedding. Hopefully this will keep the new bedding moist while allowing the casting to dry quicker and prompt the worms to migrate into the new bedding. The bottom corner (arrow) is exposed for drainage.
The Second Harvest
About ten weeks after switching feeding to the new bedding I harvested the old castings. The exposed surface of the piled casting was dry but under the surface it was still quite wet. I began at the end furthest from the new bedding and worked towards the screen separating the two halves of the bin. Initially I found only few worms but the castings closer to the middle of the bin still contained many. I found about three dozen in total and returned them into the active side of the bin
The castings contained very little unprocessed material except for tea bags, banana stems, egg shells and small pieces of wood (from the original bedding that the worms were shipped in). The former items were recycled back into the bin while the latter was separated out when sieving the compost.
The lower of the perforated ventilation pipes had been blocked with castings which had squeezed through the 3/32" drill holes. This material was wet with the consistency of mud. The upper pipe had mostly been exposed and was clear.
As the upper pipes have proved to be too close to the surface of the bedding and the lower pipes are immediately above the false bottom I will removed one pipe and center the remaining pipe midway between the false bottom and the normal surface of the castings. I completed this on the side I just harvested but the active side will wait until it's harvested.
On the active side of the bin I removed the upper ventilation pipe as the level of bedding had already dropped below it. The lower pipe here was partially with castings. When I used a wad of paper towel pushed through with a stick to clear the pipe I discovered there were also a dozen deathly worms in the material.
In the future I'm going to wrap the ventilation pipes in landscape fabric to stop them from plugging off with castings.
The bedding on the active side was made up of 1/3 corrugated cardboard and 2/3 newspaper. At ten weeks almost all of the cardboard remains while most of the newspaper has been consumed. I don't know what to make of this as others on the forums have reported good success with cardboard. I think I'll stick to newspaper in the future as it's easier to prepare too.
My Current Bin and Schedule
The lateral migration of worms into the new bedding is proving to be a slow process. I've settled on a schedule of leaving the castings piled against the grate and new bedding for four months before removing them and adding new bedding. Even after this extended period some worms are still present in the castings and are picked out by hand.
The new bedding is inoculated with a couple of handfuls of the just harvested castings in the hope that this allows some micro organisms to establish themselves before food is introduced. Feeding is continued in the old bedding for another two weeks then is started in the new bedding against the grill to entice the worms to migrate.
I have removed the extra ventilation pipe from the second side and centered the remaining pipe midway between the false bottom and the normal surface of the castings. Wrapping the pipes in landscape fabric has stopped castings from squeezing through the drill holes.
Side view showing the relocated ventilation pipes and incline of the bin for drainage. The slits in the lower middle wall of the bin hold the wire grate in place. I have never had any leakage of liquids from the bin.
Top view of the interior of the bin showing the relocated ventilation pipe now covered in landscape fabric. The left side has just been emptied of vermicompost which has sat idle for 16 weeks. The ventilation pipe was removed to clean it and it's fabric wrapping then reinstalled. Cable ties or rubber bands are used to hold the landscape fabric in place. There's also a compost thermometer in the active (right) side. New bedding will now be added to start the next cycle.
The vermicompost just removed is enough to fill a turkey roasting pan. It will sit a few days to dry out before I process it.
My last batches of bedding have been a mixture of dried shredded leaves and shredded newspaper which the worms processed about twice as fast as pure shredded newspaper. As a result I've had to add extra bedding regularly in order to complete my normal 19 week cycle. I've started adding my paper waste which would not normally be recycled (paper towels, napkins, pizza boxes) with my weekly feeding to supplement the additional bedding material.
As my organic waste is minimal I can feed in a six small pockets in the active side of the bin. Each pocket is feed three times at six week intervals during a complete cycle. Usually there is none of the last material fed remaining after six weeks but some worms are still present. For example the upper left pocket is feed at weeks 1, 7, and 13 (see the feeding record and pictures below).
I usually feed this pocket a fourth time at 19 weeks to "lead" the worms towards the new bedding. I have this vision of the worms proceeding in an orderly fashion from one feeding pocket to the next in sequence. It's probably pure fantasy but it makes me feel good ;o)
Bin Feeding Schedule
I excavate the feeding pocket by hand and pile the material off to the side.
A weeks worth of peelings, scraps and tea bags is tipped into the pocket.
The filled pocket which is the last feeding for this side at 19 weeks. It's a little larger than normal since I won't be feeding beside it the following week.
The pocket covered over and compost thermometer inserted. The new bedding in the background has some cornmeal sprinkled on the surface.
In the fall of 2009 I purchased a digital scale and began recording the organic waste I add to the bin weekly. In 36 weeks I have fed the bin a total of 25.105 kilograms for an average of 697 grams weekly.
The initial cycle on one side of the bin saw 10.594 Kg of organic waste added in 17 weeks. I missed the weighing the first feeding but by using the average of 623 grams the total weight fed calculates to 11.217 Kg. The resulting vermicompost was harvested 8 weeks later and used to start a small flow through system. At this point the material was still fairly wet and weighed 4.967 Kg.
Comparing the two weights (11.217 vs 4.967 Kg) without considering the weight of the bedding, the vermicompost produced weighed only 44.3% of the original organic waste.
I hope to continue with this and eventually calculate a weight of waste (plus bedding) versus weight of compost produced.
The cycle which started on 20100303 was fed for 18 weeks and then allowed to sit idle for 16 weeks before being harvested. The weights are summarized as follows:
Material Added
Dry Bedding - 1476 grams
Kitchen Waste - 13494 grams
Total Weight Added = 14970 grams
Material Removed
(Wet Vermicompost - 4928 grams)
(Wet Material Discarded - 142 grams)
Material Recomposted - 137 grams
Dried Vermicompost - 3117 grams
Total Dry Weight Removed = 3254 grams
The wet vermicompost was allowed to dry at room temperature for 12 days during which it was mixed and stirred several times while removing uncompostable items and rescuing worms. Discarded material consisted of mainly of tea bag thermoplastic.
This process resulted in moist material which was similar to potting soil.
Comparing the two weights (14.970 vs 3.254 Kg) the vermicompost produced weighed only 21.7% of the original organic waste and bedding.
The next cycle which started on 20100707 was also fed for 18 weeks and then allowed to sit idle for 16 weeks before being harvested. The material was drier this cycle as the lid of the bin had been left off to control fungus gnats. As a result the material was much drier than that of the previous cycle and only dried for an additional week before processing.
The total weight of kitchen waste added was 14.550 Kg and the dry weight of the vermicompost produced was 4.378 Kg. The weight of the bedding added was not recorded but using the weight from the previous cycle (1.476 Kg which should be close) the input vs output weights are 16.026 Kg vs 4.378 Kg. The vermicompost produced weighed only 27.3% of the original organic waste and bedding.
February 2012 - The bin continues to work well and has processed a total of 79.2 kg of my kitchen waste since 2009/11/04. I'm afraid I haven't been as diligent about recording the weights of harvested material so no updates on that aspect.
There was a bad infestation of fungus gnats over a period of several months. The bin was moved outside when the weather allowed and I tried several methods to combat the infestation indoors. I tried putting the entire bin in a screen bag but discovered that while the gnats couldn't fly through the screening they could still crawl through it. Other folks have reported success with this method but with using curtain sheers instead of screen. Sticky traps helped but keeping the bin drier by removing the lid and keeping a layer of dry shredded paper over top of the working layer eventually worked. I still use these measures to prevent a reoccurrence.
The bin also had a brief growth of slime mold (
