I want to harvest my worm compost, but I don't want to hurt any babies or cocoons. How do I harvest?
When the bin is more towards the dry side than the wet side. You may have to stop feeding for a bit of time. Put a small pyramid of bedding onto corrugated cardboard. Give it some time for the worms to escape into the center of the pyramid. Balance the cardboard over a 5 gallon bucket. Put the edge of the cardboard so there is a cliff for the harvested material to fall over. Select a tool of your choice such as a chop stick, skewer, Popsicle stick. Working from the edges of the pile push a bit of the material across the cardboard towards the edge of the cliff. Inspect the bit of material for worms, eggs, and baby worms. Using the tool place any worms, eggs or baby worms into a container. If the material is clear push it over the cliff and into the bucket. Repeat. When the pyramid is quite small it will be mostly worms trying to hide. Dump this group in to your new bedding. You will have lost very little of the vermicastings. Do not worry about any vermicastings that is still with the worm group as they need some used bedding to seed the new bedding.
Harvesting takes time.
Equinox posted a good way, mine is similar but a little different.
If you have any burlap, lay it over the bedding in your new bin. Spread the vermicompost over the burlap, in a fairly thin layer; 1-2".
Go have a coffee, and when you come back, the worms will have crawled through the holes in the burlap into their new home. You can easily look for stray worms and cocoons when you scoop up the compost into your holding bucket or whatever you're putting your finished compost in.
Again, spread more compost from the worm bin and leave it for a while. Scoop up the leftover castings into your bucket, looking for worms and cocoons.
I tried something sort of new for me last night. I've got two nested 18 gall. tubs top one with holes drilled in it. There's little tupperware tubs between the two to space them apart a bit to allow airflow. Over the past 6 months or so, the little tupperware spacers have filled up with casting and a ton of worms. Just noticed that last night. I scooped all the muck and worms into my plastic seed starter pots and set them in the top bin. I'm figuring the wormies will get pissed off and move back down to the bottom in a couple days, and the pots will be worm free and ready for seedlings. So much easier than making little piles on a tarp on the picnic table.
July 7 update: It was a terrible idea to put the starter pots into the bin. The worms didn't get pissed and move out. They threw a kegger and a bunch more moved in.
This post was edited by Niivek on Mon, Jul 7, 14 at 16:42
I have two systems going and I do mine inside a large dark closet. I have plastic and right beside it a factory 360. Plastic is a little tricky with the wetness . I have 3 19gal tubs , at first I just drilled holes all around bottom and sides and Im about ready to add the third tub but I have made adjustmets that Im hoping will help. As the last harvest I saved at least 50 cocoons but this is also a pain and Im thinking there were many that I missed and they went into the harvest tub. Also even though I had holes drilled I wasnt happy with worms ability to migrate, so I made adjustments
Adjustments- 1. I cut out the bottom of the tubs leaving 2-3 rim so that cut-to-fit hardware cloth could be placed in the bottom, this material is stiff so even with the weight of the bedding will not cave in. 2. I cut out windows for even more air flow and hot glued fiberglass mesh to the windows. I have spacers under the setup so air can pass thru from beneath and flow better. I used a 7/8" spade bit for the windows put 3 on each side and 2 on each end. Also if I see a lot of worms move up around the top some of may be for breeding purposes and some of it because its too wet , at that point I just I just remove the lid and/or crack it to release some air and the worms move back down. Is all I did necessary? No thats just me and what I felt would make the system a little better.
Im about ready to add the third tub and in about another month I will move the bottom harvest tray to the top put a clamp light on with the lid off, stir the mix abit and hope most of the worms will move down , might take a couple of days for this.. By this time I will hope that all the cocoons have hatched and moved into the other trays,,,, at least I can hope.
THANK YOU for the picture!
I know this thread is a little old but I like the advice here. I am new to vermicomposting but when do I harvest ? will I know when the time is right ? My bin is about three weeks old. the sides and inside top of the lid are covered with what I suppose are worm castings.
It will be a while before you can start harvesting by the bucket load. When I first started my bin, I took an old butter knife and scraped the castings off the lid and walls and tested them on some house plants. It's kind of a quick easy payoff for your efforts.
The best way to know, is when all of the bedding in your bin has turned to poop. When the bin is full of castings, you know it's time.
Here's an alternative strategy to consider if you're not a tea maker but rather a direct casting user like I am. Don't worry at all about losing worms and eggs when you harvest. Worms multiply and expand to match the space and food supply.
I have a Worm Factory 360 with a few extra bins. I keep the top bin full of dry shredded paper to keep the fruit flies out and worms down in thew lower trays. I feed in the second from top bin and I let the other bins get combed over. It takes about a month for the bottom tray to get to the 80% or better done stage and for most of the worms to have migrated higher. From there I move the bottom tray's contents including any remaining worms and eggs to a plastic container with a lid. There are at least 6 inches of space left to the top of that container, and I leave its lid cracked open an inch for air circulation. I clean the just-used tray with soapy water, create some bedding, and make it the new feeding tray.
I leave the plastic container full of castings alone for a month or more. I have even left them in place for a winter, no problem. When I want some castings for my garden I take the containers with castings and any of its worms and eggs directly to my garden and apply the castings to the first couple of inches of soil.
I see no loss in worm mass with this system and it takes very little of my time to shepherd the herd. I often see worms in my garden, too, which I very much like.