“I am starting to raise Red Euros for castings mostly. What is the best food to give the worms for the best quality castings?” ~ Rod
That’s an interesting question, Rod.
Not to be evasive, but it really depends on your definition of ‘quality’ – what type of castings do you want to create. Not all castings are created equal – but ‘different’ are not necessarily better or worse than each other in all situations.
I’m most the way through a great book called “Teaming With Microbes” (highly recommended if you want to learn more about compost and compost tea). In it the authors discuss composts with ‘fungal dominance’ and those with ‘bacterial dominance’.
The first type, which is usually produced when using starting materials with higher C:N ratios (the ‘browns’, like straw, wood chips, cardboard etc), is generally preferred by perennials, trees and shrubs. The bacterially dominated materials on the other hand are usually more effective when used with annuals and vegetable crops.
Based on this explanation, I’d predict that castings made from paper pulp might work better (i.e. be better ‘quality’) for the plants that prefer fungal dominance, whereas manure-based castings might be ideal for vegetable crops etc.
I hope you’re getting my drift here. Again, different starting materials can produce high quality castings for different plants and purposes in general.
All that being said, if you are looking for the best all-around castings, I’m sure many would argue that there is nothing better than manure as a starting material.
Vermicomposting expert, Dr. Clive Edwards has suggested that pig manure vermicomposts in particular are the best of the best – based on the fact that they seem to outperform all the others tested (in terms of stimulating plant growth – although most of their studies DID involve crop plants, which comes back to the point I was trying to make above about bacterial and fungal dominance).
Manures contain a lot of plant nutrients in comparison to say paper pulp, along with other beneficial qualities, so it’s not hard to see why they might be the best overall choice for staring material.
Hope this helps!