Well, I have to admit, I have never thought about all this...but with that said, I keep my onions and potatoes in a plastic container that has holes (got it at Target, probably) on the floor of the pantry. It works...I cook a lot and my families eats a lot so I don't have a lot of spoilage.

Well, we now know that potatoes and onions do not cause each other to spoil--one of those common-knowledge things that flat turned out not to be true. So--they can be stored together; however, the one bad apple syndrome will affect everything stored together.

We also know that potatoes and onions need:
1. Darkness, or more specifically lack of light encouraging them to grow.
2. A cool environment to prolong life and discourage mold, etc.
3. A dry environment for the same reasons.

We know they're both prone to messiness from decomposition and shedding.

Where to store? Well, I know someone who didn't want to keep them in her cool basement, so she had her father cut ventilation holes to the basement in the floor of a cabinet and stored them there. Unfortunately, my cabinet's above my husband's fly-tying bench, and he says no.

Whew, I'm glad you clarified what you meant by "the root of the problem" Your title reminded me I have to dye my hair again as the roots have become a problem :)

"How do you address the unsociability of these characters?"
Hummmm, I never thought they were unsocial. Smashed tatoes with freshly roasted garlic is one of the most social and comforting character to hit the dinner plate!

I've never thought about where they "should" go either. My roots have always gone into an antique wooden bowl. I don't buy fresh produce in bulk. Sitting around, they lose their flavor and nutritional values. So I've never had the Off-gassing or wet rot. Sounds like a fiasco I'm grateful to have missed.

Here's a pic of the social roots of the day. They all play very nicely in the same bowl. (Wish people on the various playgrounds could play as well)

I don't like using metal for the reasons you mentioned. All my roots are stored in woven baskets ... onions and shallots on the peninsula in their respective baskets ... potatoes in the lower part of the pantry in a basket. Garlic is stored in a pottery cellar on the peninsula and anything that won't fit there sits in a basket in the pantry. I use all of them frequently and rarely is rot an issue.

That last is no doubt most important factor, as mentioned by Celtin also. I typically buy the smallest bags available because they're often less expensive than the minimum amount I want to buy priced separately, but I'm also buying the problem of keeping them nice long enough with it.

Maybe the best storage would only hold a max of a 5-day supply, whatever that was in each kitchen, and thus could be made of anything and set anywhere.

I won't have wicker, in spite of its charm, but baskets do allow some air circulation down low to help keep them dry. They also have no solidly flat surfaces for veggies to lie against that could encourage dampness.

Rosie, why not wicker? I place a napkin in the bottom of the onion and potato baskets just in case.

I keep mine in a drawer next across the aisle from the prep area. I use them often enough that they usually don't go bad and if one is starting to soften or mold, it gets caught and thrown away before it gets messy. The onion skin scraps get pulled out on occasion and if necessary, the drawer can be pulled out and turned over to get any tiny flakes out. It's dark and as cool as any place in my house outside the fridge. Our old cabinets had a drawer in about that spot that was melamine (or something white and plasticy) coated in about that spot so I got in the habit of keeping them there. The wood drawer in our current cabinets is working fine.

I keep the garlic in the spice drawer, just because it is convenient, but perhaps I should move it to the onion and potato drawer so I don't have to clean out the bits of garlic skin that flake off.

Bottom fridge drawer in my prep area. Onions, potatoes, garlic, and sometimes the carrots. With the ale. I don't think they benefit from the ale, or vice versa, but they don't mind sitting on top of the shoulders of the ale bottles, and the danged ale has to be refrigerated, dang it.

Aliris, do they really last for you out of the fridge? They don't for me. Also, colder onions and garlic are easier to peel and aren't as tear-provoking.

This is how I plan to store mine. I saw these on another gardenweb thread. Merry early Christmas to me :)

Here is a link that might be useful: Onion, Garlic and Potato Storage

OK, so potatoes and onions are fine playmates. Bad apples, OTOH, are a problem. Everyone gets along with cold ale (isn't the wet sides of the bottles a problem? Plus, I prefer my ale room temp, but that's OK).

Plllog - I am having a hard time analyzing the experiment: 'do these last'? I think "these" is a very moving target. I think when onions come from the store the freshness is hugely variable. When they come from a farmer, though, they can vary a lot as well - sometimes soggy in which case they won't last, quickly. I've had some that go on and on though. I just can't really quite make out what determinants really are at play. I haven't made a careful study but it's bedeviling enough that I just might (though I know I won't; I'll rely instead on all this seemingly-knowledgeable hear-say. Life is just too short...)

Thanks, all, for the explanations and photos. I haven't yet seen any eureka! product for my needs, and I I'm thinking creativity will be adequate -- that is, there don't seem to be obvious rules beyond - air flow, darkness, coolness. I don't think anyone's worked out the ideal mousetrap yet for this, seemingly. I wonder if there are wicker colanders? I think that might be ideal - small, non-metalic mesh....

Plllog, I may have relatively good unrefrigerated luck due to our microclimate - at the base of a hill (=wind generator), relatively close to the ocean things are often fairly refrigerated ambiently around here. Couple that with dh's obsession with growing shade and lath-and-plaster on at least two rooms, plus high vented ceilings, and the house stays pretty cool all on its own. For example, I'm freezing right now.... (indicating it's time to go hang out some laundry, boost the vit D levels, dry the clothes and stir the blood into warmth in one fell swoop).

Root vegetables I store in one of the fridges most of the time.
Except potatoes. i eliminated potatoes.

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In the far distant future someone may make a root cellar compartment (drawer?) in an appliance. It will have the right humidity and air movement, keeping roots unrotted. It could have several compartments.

I once bought a 100 pound cheese, which gradually rotted while it was being consumed. I found out later that my fridge humidity was too high for this cheese.

I think the humidity level is ultimately as important as the temperature. That and the air movement.

I have something to show that I think might work. Please forgive the not-perfectness.

It starts by understanding that this is a colander I have loved a lot for a long while. I didn't have it new but found it in a second hand shop long ago while homesick -- my mother has one just like it and for some reason I just wanted to have one as well. Like my mother's it's not very high quality. It's thin and bends and mine is even cracked now on the bottom (actually, I think you can see one of the cracks in the front as well). Eventually one foot of mine has broken off (like my mother's as well!) and so works even more poorly than ever. Still I haven't wanted to give it up.

So I was thinking about those plastic metal-covered drawer-thingies ... and I realized I have this riser and the remaining two feet of the colander fit into the slats and turn the whole thing into a 'drawer' that even tips forward, which is just perfect.

Here it is closed:

And here it is tipped forward; this is actually stable:

I'll give it a whirl. While dreaming about the beautiful crocks!

I had a client who modified a Craigslist wine cooler to hold her veggies. She had a large enough pantry it went in there. I thought it was overkill, but she's happy with it.

I use a recycled plastic 2 gallon ice cream container to hold my onions. I punched a couple of holes in the sides for air and leave the top open. It's in my pantry, because it's ugly. I use two of them for 5 pounds of potatoes. (I use the same ice cream containers to hold my compost scraps too.) I leave the bottom plastic alone, because I've been known to not use them often enough and then there is something black mushy and funky needing to be disposed of. Then the yuck goes to the compost, I rinse the contaminated bucket, and it goes to the recycle heap.