This may not be the post you were expecting to see if you're looking for step by step directions. I've been asking the question myself lately. How to harvest worm castings? Why have I been asking this? I have some friends working in soil food web testing labs. They are finding that many worm castings they've tested are surprisingly lacking life. We're all told how worm castings are the best thing for plants and soil. How can it be if they're so lacking in life? I began investigating and found a quote from Elaine Ingham:
Feb 15 2016
Worm castings do not, willy-nilly, have more beneficial life than compost. I've been unfortunate enough to have looked at "worm castings" that are just as bad as the worst manure you have ever seen. So you can't trust people to manage worms right either. However, if they do manage the worms aerobically, with good fungal foods, then worm castings and thermal compost and static compost can be every bit as good as the others.
How do you tell? MICROSCOPE
Elaine R. Ingham
President, Soil Foodweb Inc.
Ok, so I know some of the worm farmers whose tests were lacking life. These folks are doing a pretty good job of keeping beds aerobic. They're adding what are considered fungal foods. What's happening?
I continued to investigate, something was missing.
I was asking a lot of questions of worm farmers about methods: How do you harvest? How wet are your bins? what do you feed? what's your bedding? The answers varied greatly but their tests were coming back similar.
Next I turned to the laboratory owners/workers. How are the samples arriving? What life is lacking most frequently? Consistently fungi and nematodes were the most often lacking organisms.
Finally I had something consistent, a trail to follow.
Eventually I had a conversation with Vivian Kaloxilos a student of Dr. Ingham who does soil food web testing in Quebec, Canada.
She made me feel like those cartoons where the lightbulb pops on above your head when she said:
"I asked a client to send me her sifted and non sifted vermicompost. I found twice the amount of fungi in the non sifted, plus tons of nematodes. In the sifted, the fungi was much lower and nematodes were barely present. This brings us to the issue where vermicompost producers need to harvest their worms and eggs from their product before giving it away. Its a catch 22"- Vivian Kaloxilos
This was what I'd been searching for! It would seem drying vermicompost to screen it or perhaps the agitation of screening was damaging the organisms in the castings!!
Now this begs the questions: How do we harvest castings without doing harm? Does the aesthetic appeal of finely sifted castings matter? How do we not give away cocoons or baby worms and still sell the best quality castings?
I'd love to see the readers comments and suggestions on this!!