Pre-Composting Then Vermicomposting
Here is a really good question from Bobby:
I really enjoy your website and have learned a lot. I have
2 old weber bar b que grills with attached tables and wheels works
great. I am thinking of putting all “food” in a compost pile for a
week or two and then feed that to my red worms. It seems it would be
easier to control quality and quantity of food. What would be the
advantages and or disadvantages of this method?
Thanks
Hi Bobby,
Not 100% sure I follow how you are using those grills for a vermicomposting system – but it sounds interesting nevertheless!
You are absolutely right – composting food waste for a short period of time (often referred to as ‘pre-composting’) before feeding it to your worms is an excellent strategy, but of course there are a few disadvantages as well. Anyway, as per your request, here is a breakdown of the pros and cons of this approach:
-
Advantages of Pre-Composting
- Partially breaks down materials, so faster vermicomposting
- Microbial colonization of wastes, so lots of food for worms (and less lag time before worms start processing it)
- Allows you to deal with excess amounts of waste and control amount given to worms
- Helps to avoid overheating in vermicomposting system
- Can kill weed seeds and pathogens (when present in your waste materials) if large enough volumes are composted
- Lets you create the ‘ultimate’ worm food mix before it goes in the worm bin
-
Disadvantages of Pre-Composting
- Requires that you have a yard and space for composting
- Can lead to infestations of outdoor pests (house flies, fruit flies etc etc) in your bin if enough there isn’t enough heat generated during the composting stage
- If not properly handled, materials can go anaerobic and be unpalatable for your worms
- Takes extra effort
As you can see, if you have the space and are willing to put in the effort needed to compost the materials properly, pre-composting can be a great strategy.
Hope this helps, Bobby!
Technorati Tags: composting, pre-composting, hot composting, vermicomposting, thermophilic, worm composting
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Written by Bentley on August 12th, 2008 with
7 comments.
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282 lb of Food Waste, and Counting!
#1. August 14th, 2008, at 4:48 AM.
To set the stage, I’m raising eisenia fetida in my garage in three 30 gallon plastic tubs. I harvest the compost at a rate of one tub each month.
I’ve been experimenting with pre-composting worm food for several months now. I started by using material directly out of my compost tumbler which consisted of about 50% completed compost plus material in all stages of breakdown since I add garden trimmings, grass clippings and overripe vegetables on an ongoing basis. The worms do just fine with it and I don’t have an excess water problem in the worm tubs but it’s a much denser food and I had to cut my quantities at feeding time about in half. Overfeeding this stuff doesn’t bother the worms but it does reduce the quality of the vermicompost somewhat.
About a month ago I was given a half watermelon that was past it’s prime. It was’t a good time to feed, so I chunked it up and layered it into a 24 qt plastic pail with a pile of 1″ squares of cardboard from a cardboard box. The mix was about 25% cardbord and the balance watermelon. I laid a piece of plexiglass over the top of the pail to keep the flies out and promptly forgot about it. About a week later I remembered it and found the bucket was only about half full. The watermellon was reducing and giving up water. I poured of the water, which was cloudy and smelled like vinegar, then dumped the contents back and forth between two pails to areate it and put the plexiglass back over it for another week. It further reduced to a little less than a third of the pail. I poured off the water again and fed the remains to my three tubs by laying it on the top of the bed. When I pulled the covers off the next day to check the worms, I almost couldn’t see the food for the mass of worms all over the top of it. This was true of all three tubs.
I have just set up four more pails as follows:
1. Watermellon and cardboard (to duplicate the test)
2. Watermellon and chopped wheat hay
3. Squash/cucumber and cardbord
4. Squash/cucumber and grass clippings
I’ll get back to you when I have more results.
I hope there’s something helpful here.
John