Really great questions from Sherman:
Hi, I read that red wigglers consume microorganisms rather than food waste so how does having more worms consume food wastes faster?
What types of kitchen food waste’s good for supporting the microbial population?
Thanks for writing in – this is a really interesting topic for discussion for a number of reasons.
OK – let’s start with microbes as worm food…
Yes, it has been shown that worms derive much of their nutrition from microorganisms that have colonized decomposing organic matter. I think part of the problem here is that these worm composting facts – in this case legitimately based on actual scientific research – can be viewed in too-rigid a manner. i.e. Worms eat microbes, that’s all they eat, and THAT’S THAT!!
While I would absolutely agree they likely get most of their nutrition from all those microbes – the fact is, they are definitely consuming more than just microbes (thereby getting nutrition from more than just microbes as well).
The microbes are using enzymes to break down the food materials – in the case of fruit and vegetable wastes, for example, this would involve the rupturing of cell walls, and the release of water (along with plenty of nutrients for the microbes to “feed” on). So you kinda end up with this slurry of stuff (for lack of a more scientific term – lol) that’s full of microbes.
Well, picture the worms coming along like a Hoover and sucking up this slurry, microbes and all. Yes, much of the nutrition will be locked in the microbes themselves, but there’s no doubt they are ingesting a lot of the waste material as well.
It’s as though the microbes are softening the food for the worms, and the worms are saying “thanks” by eating them. lol
OK – on to worm numbers and how that affects processing speeds…
In theory, if there are more worms there are more “mouths to feed”, so more wastes can be processed. In a well established system, using foods that have been well-optimized (i.e. made even more microbe-and-thus-worm-friendly), this can definitely be the case. But the problem is that people (often newbies) tend to take this too literally – assuming they can start a system with loads of (usually poorly optimized) food wastes and loads of composting worms, and that everything will work out great as a result.
Unfortunately, that’s very rarely how it will actually work. What usually happens in cases like that is that the food wastes become foul, heat up, give off toxic gases etc, causing the already-stressed worms to either die or attempt to escape the system.
My recommendation is always to start with a modest population of worms, and modest amounts of optimized food materials (along with plenty of bedding), and to gradually ramp things up from there. These worms will grow and reproduce very quickly when they are provided with a scenario like this – and you can end up with a large, thriving population of worms that CAN process lots of wastes quite quickly.
Let’s talk briefly about kitchen scraps…
Obviously, the usual composting rules aside (i.e. “no meats, dairy etc”), ideal kitchen scraps are those that come from water-rich foods (fruits and veggies), and that have been optimized for microbial colonization. Something like a whole carrot, for example, is pretty much useless as a worm food. For one thing, it’s a root vegetable so it is designed for life in soil! If anything, it would probably start growing in your worm bin. lol
When you chop, freeze/thaw, cook, age etc resistant wastes like this they become exponentially more microbe-and-worm-friendly (especially if you use a combination of tactics). As alluded to, some scraps need less optimization than others. eg there is a big difference between putting some rotting lettuce, or a slice of watermelon into a worm bin, and dropping in a whole potato!
And speaking of potatoes…
Starchy wastes – especially ones high in salt – are a lot less ideal, but it is still possible to process them (in moderation) in a vermicomposting system. The best approach is to chop them up really well and mix them with the variety of other optimized wastes.
Anyway – I hope this helps, Sherman!