'blackening' worm castings...

[King, North TX]

First allow me to apologize if this is the wrong place to post this query.

 

I've been helping a buddy of mine start up his worm farm. He's working on a system of animal waste management that delivers 100% organic fertilizers and compost.

 

My question is how do we, or rather what do we feed the worms to create 'darker' castings? We've been tinkering with the nitrogen levels, trying augments like blood meal and slaughterhouse 'fruit punch' (blood and water mixture) during the composting, but we're not there yet.

 

Any suggestions from the Chemistry Community?

 

Thanks.

 

(http://www.northtexasorganics.net/)

[ewmon]

Why do you want darker castings?

[King, North TX]

Why do you want darker castings?

 

It is partly for marketing purposes... Worm castings are often called the "black gold" of fertilizers, and ideally they should look like coffee grounds.

 

Our's don't, yet...

 

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I tried to attach a picture of what we've produced thus far.

[spookyjeff]

Perhaps a derivative of animal urine?

[King, North TX]

Perhaps a derivative of animal urine?

 

After a few forum searches, I've come up with 2 additives: "biochar" and "dried molasses." *Another poster recommended simply giving the worms more time to do their thing, as they re-ingest the material it gets darker.

 

What component of the urine do I need to isolate?

[spookyjeff]

The urea of the urine has the highest nitrogen content and is an excellent fertilizer by itself. If you try this method I'd start off with low concentrations and go from there. I don't know any methods of extracting urea though I'm sure with some searching you'll find a method.