Tuesday, July 6, 2010

A hole above the ground

Necessity is the mother of…Repulsive 2010 beta.

My usual spigots can’t handle grubbery leachate; it's pretty nearly sludge, thinner if the filter hasn't been dislodged yet but always muddy and with fine-silt particles that clog the tap. I can’t lift a full inner bucket right now to get at the lower one to empty it (wrist injury’s healing, but not yet fixed). And letting the reservoir back up into the unit is not an option. So I set the inner bucket on top of a soil-filled planter that had once been fitted out as a wormery--which means that it had ventilation holes on the sides and bottom, plus a drip-tray beneath. Also, since Verne has no concept of personal space or respect for ancestral colony gravebins, some worms.

This largish unit has about the same volume of soil beneath as potential food-and-grub volume above, and I’m not sure I’d try much less than that; eight inches of soil minimum, if my admittedly sketchy math is correct.

So far, it’s working quite well. A few grubs have no doubt squirmed into the soil, but most of them stay near the top, that being where food comes in. (I decided not to worry about it unless or until I saw a grub using the wormery part to escape; so far, no grubs have been sighted emerging from the soil layer or hatching in the soil-packed vent holes, and the mamas don't tend to bother probing them.) It's quite possible there are worms in the grubbery's inner bucket, but that's not a problem either, and the holes are there should any aggregate bit decide to move. Leachate seeps out of the grubbery into the soil, where it serves to keep the worms fed and moistened, and since soil regulates temperature and pH, there’s no need to worry about Verne no matter what the grubbery gets up to. Too, between the weight of the soil and the nesting of base and rim, plus the inevitable-here-in-Bucketville weight on top, the grubbery’s as nearly secure as I can make it. No human-perceptible odor escapes except when it's very wet--as in, after our recent storm-cycle--and then it smells like fertile wet soil, no trouble at all. Judging by the adults flying around, happy-BSFL pheromones are being produced and food-scent is perceptible to them, since despite crawl-off there's no population shortage on the horizon, but so long as my neighbors and I can't smell it, it's a success.

I'm kind of excited: a moisture-regulating grubbery means one less chore, and one less chance I might accidentally spot one of the aggregate bits that earned Repulsive his name. Well worth the temporary reallocation of a bucket of cheap dirt! Have to say, I’m not sure how well it’d work without worms in the soil layer and/or EM in the foodstuffs. Or, ideally, both. But since I do have both, this is a workable model for me.

At some point, of course, I’ll have to do something with the unit, but with any luck at all, that won't be until fall. Lure the last layers to an alternate location, let the grubs in the unit mature and crawl off or go dormant, let the worms work the bucket over the winter, and in spring and harvest a bucket or so of rich vermidirt and worms. From stuff I wasn't willing to feed my bokashi buckets.

The obvious next step is to test this as an urban pet waste disposal; I've had some success with temporary in-ground units, but that only works where you have a hole in the ground away and downslope from your garden! Too, that was to get rid of the leavings from the neighbors' dogs. The household feline's box is a very different matter. EM, obviously, but what then? I'd thought about BSFL before, but they don't like clay, and there remained the question of what to do about the remains in the bucket once they'd done their part.

Worms were also a possibility, of course, but they can't handle fresh liquid wastes. Grubs + worms seemed reasonable, except for everyone saying how difficult it is to maintain them together.

We shall, as ever, see.

Glad to be back,

Photo courtesy of USDA Natural Resources Conservation Service , where some very odd photo categories can be found!


jolene said...

First, let me tell you that I love your blog! I just finished my first "baby batch of bokashi bran" as per your recipe. The first handful is in my bucket.

Can you give me some advice? I've successfully made it through my first round of bokashi. I finished it off in a container (an old plastic tote with holes drilled in the bottom, no lid) in between two layers of soil. I just checked on it after its requisite 3 week curing period. I have since learned A LOT about black soldier fly larvae. They're loving my bokashi finishing tub.

So, I have a few questions. Does this mean the BSFL will eat all the goodness and I won't get any proper compost out of this batch? I don't really mind too much- I'm primarily concerned with keeping all of my foodwaste out of the landfill. BUT I was really looking for some awesome compost for my container gardens.

What do you suggest? Should I cover my plastic tote with its lid for the next batch? Will that keep the BSFL out? Do I want to keep them out? I was skeeved at first, but now I kind of like the little guys.

Thanks again for your great resources!

D. S. Foxx said...

Hi, Jolene, welcome to bokashi!

The finishing technique you describe is usually done with a bag cover to keep out excess moisture and insects. Since it will also keep out worms, I don't do that myself, but if I were finishing my bokashi in a garage or something, I would. I've done lids with and without weights, and far prefer to use a weight to compress the material, plus a cover to keep out flies, and at least two inches of soil on top of the bokashi. YMMV.

Re: BSLF in planter finishing bokashi--it's not ideal if you want great soil, but you'll still get very, very good stuff. With enough soil, especially on top, the composting process can "outrun" some of the grubs, so you get a better ratio of organics to inorganics, but grubs don't eat quite everything, and what they leave is broken down enough to make soil microbes and worms happy, which in turn makes plants happy once it's matured. You're not going to get proper compost out of a planter-finished bokashi scenario anyway; what most of us think of as compost doesn't include any soil to speak of. But planter-finished bokashi that's been grub-gobbled is actually closer to compost than planter-finished bokashi that hasn't yet been found by macro-digesters.

Confused yet? -G- There are two primary reasons to keep BSFL out of your finishing unit: if you're aiming for large quantities of finished product, do anything you can to discourage the things. And if you're planning on using any of your finished product indoors, it's a whole lot easier to keep them out than to try to get rid of them later. A heavy layer of soil will eventually kill a BSFL colony, as few of the grubs mature and few of those return to lay eggs, but it's a slow process--and in the meantime, you have to expect the odd mature grub outside the planter.

Which is really disturbing if you happen to grow herbs on a windowsill in your kitchen!

If you're exclusively a container gardener and you don't have friends witha compost bin or a community garden that accepts compostables, you might want to keep the BSFL around--after a while, you have enough finished or composted bokashi for your garden, and then you have to find something else to do with your pickled kitchen waste until it's time to refresh your planter mixes. Plus, you can feed them stuff you don't want to compost (pet wastes do quite well with bokashi and BSFL, as do materials too spoiled for your bucket). Just keep them contained.

blacksoldierflyblog.com has lots of info about BSFL, if you're interested.


jolene said...

Wonderful- thanks for the advice! It's actually been really hot in Virginia over the past week- up to 106 yesterday (and we've still got a month of brutality to go). I'm not sure yet, but the BSFL look a little worse for the wear. Maybe the heat will keep the colony in check.

If they survive, I might try to "self harvest" and see if I can find a friend with chickens looking to trade :)

Next go round, I'll try finishing it off with a lid. I'm chronicling my adventures at makethingsgo.blogspot.com

Thanks again!

jolene said...

They've returned! Here's my post about colony #2. Upon reading your suggestions again, it was totally my fault for not following your directions properly (I just put the tub lid on and some bricks on top of THAT. Duh!). But I kind of like them.