Q. You've mentioned on the show that you are 'vermicomposting'. Me too; I made my own worm bins from large plastic totes, and they work well. My only complaint is that separating out the finished compost is time-consuming and tedious. You've said that you use a stackable 'Worm Factory' for this very reason. Do you find that it makes it easier to harvest the finished compost? Do the worms really crawl up from the "finished" trays into the next higher tray? Do you have a problem with escapees? And finally, how do you store the compost produced in the winter? In short, I would love to hear a segment about your vermicomposting! And thanks for all the wonderful shows you already do. I listen to your podcast every week.
--- Sue in Detroit
A. Well, thank YOU, Sue. I've had my "Worm Factory" for a little over two years, and it has been a real blessing—especially in the winter.
In the summer, I can just carry our 'compost crock' (where I keep my kitchen scraps temporarily) out to one of my sealed black plastic bins, dump it in, add a lot of shredded leaves and be done. (I never add potentially vermin-luring kitchen waste to one of my open piles; they're for shredded leaves and coffee grounds only.)
But easy access to those bins often becomes perilously difficult in the winter, especially a wretched winter like this year of endless 'Snowmageddons'! So I used to keep a galvanized metal 'slop bucket' with a locking lid outside, fill it with kitchen garbage and then try and mix it into my compost bins with big batches of shredded leaves I had hoarded for that purpose. But when temps had been below freezing for awhile, this was an ugly endeavor. I broke the bottoms of three slop cans trying to bang those frozen garbage sculptures of R2D2 out. And then the frozen chunks of' muck would just sit there like a rock in the middle of the pile until June.
There was also the realization that most kitchen garbage doesn't contain enough potential nutrition to improve the finished compost very much. Only coffee grounds and eggshells really perk up the mix in a regular compost pile. But I also realized that you can't—or shouldn't—throw away all that other kitchen waste; the essence of a sustainable landscape is to re-use as much organic matter as possible. And I knew from research that specialized redworms could turn that mostly worthless compost waste into a super-premium plant food. (One author of a paper on the staggering increase in nutrients that occurs when garbage is processed by red wigglers concluded: "Something wonderful happens in the gut of a worm.")
So I abandoned my winter garbage can dance and ordered a worm tower—specifically for the first reason our listener brought up; that is, the separation of the finished product (more properly called 'worm castings' than 'compost') from the stuff that's still pretty raw.
In a single bin system, you're supposed to have 'lanes' you can manage. The first lane in, say, a big Rubbermaid bin that you've equipped with some kind of drainage system would be a layer of garbage, covered by damp, shredded newspaper and then damp sheets of newspaper. Then, when you have more garbage to add, you make another lane next to it and so on. When you put in the final lane of fresh kitchen waste and dampened paper, the hope is that the worms will have finished with the first lane, and moved over to the side with the fresher stuff.
But how are you actually getting this hopefully-finished stuff out? With your hands? A little shovel? I found this concept daunting enough that I never tried it, and instead went straight to the acquisition of my 'tower', which uses stackable trays instead of lanes. (It also has a solid bottom that funnels the 'worm tea' into a spigot, and a lid to keep light and flies out.) You fill the bottom of a tray with fresh garbage, cover it with lots of shredded newspaper, wet it down, put a few sheets of damp newsprint overtop of that and put the cover back on. Then you keep filling trays as the need arises, always putting the freshest material on top.
And the worms really do move up. They'll keep working finished material if that's all they have, but they really seem to prefer fresh garbage, and start moving up as soon as I put a new tray in place. And they have no trouble climbing; the trays are apparently designed to make upward mobility easier.
And I've never had a 'loose worm'; no 'escapees'. I do see the occasional worm when I lift the top cover, and I have had to rescue the occasional swimmer from the 'worm tea' reservoir at the bottom, but none have ever tried to make a break for it. They want to stay in that dark, moist, food-rich environment.
And what do I do when a tray is finished—that is, turned into pure castings? Well, there's always a few worms still working in even the most finished tray, so first I'll pick out as many as I can and toss them back into the bin. Then, if its summertime, I'll empty the contents of the tray at the base of one of my fruit trees or split it up between a few tomato and pepper plants. In the winter, I dump the finished trays into one of my compost bins outside, where the worm castings will make my already excellent compost super-excellent!
And if there's two feet of icy snow on the ground? I just keep filling new trays and leave the finished ones in place until I can access my compost safely again. Getting a bunch of extra trays turned out to a great idea this winter; and with each new tray, I'm building a wormy Stairway to Compost Heaven!