Batch Vermicomposting

A question from Michael:

How long does it take (in general) to finish vermicomposting a batch
of kitchen scraps? I just started my first vermicomposting tub a few
weeks ago, and was wondering how long I should wait once I stop
feeding scraps before I separate out the worm and collect the
castings.

I realize I will most likely want to start a second tub so I can have
one that I am currently adding to and one that I am getting ready for
harvest, but it might be nice to have an idea of how long it’s going
to take so I can plan for my second tub..

Hi Michael,
That will be dependent on a LOT of different factors, so there definitely isn’t a firm answer I can give. The quantity of worms you are using, the bedding type, oxygen availability, your scrap handling methods (freezing? aging? blending? etc), the temperature, moisture content, types of food wastes added – these (and more) will all be deciding factors.

I frequently have tubs with very high concentrations of worms, ready to be quickly harvested for local customers – it is amazing to see just how quickly the worms can convert wastes into castings in these bins. It’s almost like I can’t keep them fed! haha

A bin FULL of shredded cardboard, bulky food wastes and 1/4 lb of worms on the other hand will likely take a couple of months (and that’s assuming conditions are otherwise conducive to successful vermicomposting).

Your best bet is to optimize as many variables as you can, and simply observe the system over time. With adequate worm numbers, warm/moist conditions, lots of easy-to-process waste materials/bedding, and good air flow, it is not unreasonable to expect to see a fairly well processed bin within a few weeks. There may be a fair amount of undigested materials on top due to drying out etc, but these can easily be removed and added to a new system before harvesting.

Anyway – hope this helps!

Written by Bentley on May 6th, 2009 with 4 comments.
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