I just sort of think my worm bins as mini composting piles (which is really what they are). I think of the bedding as being the "browns" (carbon - carbohydrates)...to balance out all the other stuff we put in as worm "food" which happens to be mostly "greens" (nitrogen - protein). Remember you are essentially feeding a whole foodweb of life... the worms just happen to be biggest ones in the bin and they depend upon the little guys to be happy.

Besides another way to look at a worm bin is as the worms' toilet bowl ("You're living in a sewer, Frank." a line from the movie Bullet, if you're old enough to remember)... I'm thinking its probably best to "dilute" the poop from time to time... I put a small layer down on top every so often just so the worms can crawl up out of the sewer if they chose to plus it covers over weeks worth of rotting organic foodstuff that more annoying pests would like to breed in.

I don't know if its necessary but I just do it. My choice for bedding is rehydrated coir and some shredded cardboard/paper on top of that...

"Browns" and "greens" don't play a role in vermicomposting the same way they do in hot composting. Hot composting is a process you want to avoid having in a worm bin. The bin conditions need the right combination of darkness, moisture (70% plus or minus), thorough oxygenation, and the right temperature range for the worms to live, thrive and eat. In addition, the bin needs to be free of the noxious products of anaerobic decomposition.

Bedding eventually becomes food for worms, but the purpose of bedding is to hang around long enough to absorb and distribute moisture, and to provide aerated channels throughout the bin material, so that decomposition remains aerobic, and so that the material around the worms always has plenty of moisture and oxygen. Depending on what exactly is in your feed stocks and the other specifics of the bin (i.e. how shallow it is, how much drainage there is), these aims *may* be achieved without adding bedding, but it is usually tricky to do so with food scraps, which have lots of moisture and lots of nitrogen, so that they can create bad conditions for the worms, either by inadvertently feeding "hot composting" bacteria which raise temperatures above what worms can tolerate, or by feeding anaerobic bacteria, which create smelly substances toxic to worms.

From my observation, worms don't have a problem living in their own castings. In fact they seem quite happy living in highly processed vermicompost for a lot longer than you'd think possible - it takes a long, long time for them to thoroughly strip out all the nutrients they can use (like many other creatures do, worms eat their own poop over and over again), plus the vermicompost is nicely granular and moisture absorbent, so it has a good air/moisture balance for them without a need for bedding. This probably also explains why commercial vermicomposting operations have such good results with hot composting materials first, and then feeding them to the worms directly with no bedding. I will always find a good population of worms in the most processed trays of my worm bin (so much for the claim that they will all move out on their own) although you don't get the most dense "spaghetti" type clusters of worms in those trays if there are other trays with more density of food available.

What I have noticed, worms seem to be happier when the bin is covered with damp shredded paper. They hang out just below the surface of VC and under the shredded paper layer. As when there is nothing covering it, they are burrowed deeper, even if there're still food on the surface. The VC is also different. Not enough paper, and the VC is more dough like (sticky) as suppose to crumbly. I also think, damp shredded newspaper provide them with a moist environment with ample O2.

I remember when I first started always having machine shredded newsprint mixed in the bedding and some hand stripped paper in 1" widths for a cover, plus I would add a layer of hand stripped each time I fed to cover. But now I dont use any hand stripped paper, I just put layered paper on top of bedding. If Im feeding a very wet feed I will have a layer of paper under and over it to soak up some of the moisture. I prefer to not have so much liquid draining thru all my trays,, thats just me. When it comes time to harvest my bottom tray if its too wet I have to let it dry out before I finish with it. Like others have said you will get a feel for it as time goes by

Rule of feeding-- How I did it in the beginning was place a little food in one corner of the bin/tray. I find that worms will first eat from the bottom of a food mass and then move on top, once I see a lot of worms on top of the food I will then place food in another corner, because it will take a little time for the new food to break down. You need to be aware that the worms dont eat the food you put in but basically the bacteria that breaks it down, so with that knowledge everything will go faster the better its broken down. If the food is broken down into a slurry or mash it can be used sooner. Everyone has their own method of bedding and feeding, but I save up my scraps then run it thru my juicer and if the pulp is a little on the dry side I add the juice back in.

hummersteve, About a month ago, during a month of below freezing weather I moved one of my bins (22"x 28") inside to prevent freezing. After warming up for a few days I wanted to try the horizontal migration method to allow me to harvest some castings. I had never really tried that method before. So I moved all of the material to one end of the bin, then added some shredded newspaper to the empty end. On top of the new bedding I added a mix of shredded newspaper and aged kitchen scraps and didn't add anymore food to the processed end.

Well within a few days most of the worms had moved into the new bedding /food mix and were having a feast. I left the bin alone for another week, then harvested about 2 gal. ( 12 lbs.) of nice castings from the processed end. Used the pile/sort method to recover the worms (about1/3 lb) to place back into the bin. I was really pleased with the results.

I also wanted to try starting a new small 2 gal. tote to get an idea of how fast the worms reproduce - something that seems harder to get a feel for in a large bin. Only placed a small handful of worms into the new tote. They seem to be doing really well and look pretty fat. In fact they appear to be fatter than those in the larger source bin mentioned above.

I'm wondering why seemingly healthy worms in the source bin are thinner. Do you think the source bin could be over-populated? I've been feeding both bins with the same scraps. Have any of you noticed any connection between the size of the worms and relative bin density, feed sources etc. I'm always cautious about over-feeding so don't want to add more food under the assumption that the worms are "skinny" because I'm not feeding them enough.

Harry