My mother saw me stacking potatoes right next to a bag of onions in the pantry and just said, “Don’t put that there.” I asked why, and she said her grandma always kept them apart; no idea why, just always did.
I laughed it off at first, just a kitchen thing. But then it hit me: if that’s true for a bag of onions sitting out for a week, what’s happening inside my stockpile, where things sit sealed up together for months, sometimes years? I’ve been building up long-term storage for a while now, shelves full of buckets and cans I’m pretty proud of, and I realized I had no idea if I was making the same mistake, just slower and out of sight.
That’s when I picked up this book, wanting to know what else I’d been getting wrong without realizing it, and honestly it wrecked my confidence a little. I’d had salt sitting against my canned goods for months without thinking about what that was doing to the seams, and a jar of homemade pickles parked right next to a shelf of metal lids that had no business being that close.
Even my grain stores were a mess, a fresh bag of flour shoved next to an older one like that wouldn’t matter, when really I was just giving whatever was already living in the old bag a way into the new one.
Don’t make the mistake I made!
15. Onions and Potatoes
Both want the same cool, dark corner, so everybody stores them together, and both spoil twice as fast for it. Onions give off moisture and gas that push potatoes to sprout, while potatoes push moisture back and rot the onions from the skin in.
What you can do is split them up on opposite sides of the room, and keep both in mesh bags or slatted crates instead of sealed plastic, which just traps the damp. Keep the potatoes in the dark too, since light turns them green, and that green is the plant building up something you don’t want to eat.
Funny enough, the same potato you’re carefully storing away has another use most people never think about. Got a cast iron pan that’s rusted past the point of caring? Grab one from the bin and try this weird potato hack before you throw the pan out for good.
14. Apples and Root Vegetables
An apple in the root cellar is a small ethylene factory, breathing out ripening gas around the clock. Anything sensitive stored nearby, onions and other root vegetables included, ripens along with it and rots early.
There’s one interesting exception though. Tuck a single apple in with stockpiled potatoes and that same gas holds off sprouting instead of causing it.
Also, if you want root vegetables to stay fresh for a year or more, here’s a wood ash trick I’ve been using for years that makes it possible. It’s kept me stocked with fresh carrots straight through winter, no greenhouse required, no fussing over exact temperatures. Just layer them in a wooden box packed with wood ash, keep it in a root cellar or a cool pantry between 32 and 40 degrees, and you’re good to go.
13. Whole Wheat Berries and Already-Milled Flour
People treat these as interchangeable and store them shoulder to shoulder, but they don’t age the same.
As a matter of fact, milling exposes the wheat germ’s oil to air, and that oil goes rancid within months. On the other hand, whole berries, sealed and kept cool, last decades.
Store flour in small batches you’ll use soon, keep the bulk of your grain as unmilled berries, and mill only what the next few weeks call for.
12. Honey and Metal Lids
Honey is acidic and pulls moisture from the air even through a decent seal, and over years in storage that combination corrodes metal lids from the inside out. It’s also one of the strongest odor absorbers in a stockpile, more so than your powdered milk.
Why You Should Always Keep a Jar of Onion and Honey Around
(You’ll Thank Me Later!)
Store honey with plastic lids where you can, keep it away from strong-smelling neighbors, and check any metal-lidded jars yearly for rust starting at the rim.
11. Strong-Smelling Foods and Powders
Onions and garlic scent everything around them, and cumin isn’t far behind. Powdered milk, flour, and sugar all drink that smell in and hold it. Coffee works both ends, giving off its own aroma while soaking up everyone else’s. Seal the loud stuff separately, and keep your powders across the room in glass or heavy Mylar, since thin plastic bags might as well be left open.
10. Dried Mushrooms and Anything Aromatic
Dried mushrooms absorb both moisture and smell harder than almost anything else in a dry pantry, worse than powdered milk in both directions. Store them next to onion powder or dried herbs and they’ll taste like the shelf, not like themselves, in a matter of weeks.
This goes for cordyceps too, which feels like it’s everywhere in prepper circles lately, half the people I know have started stockpiling it right alongside their culinary mushrooms. Most of them are storing it wrong, since it picks up odors just as fast as the rest.
The best way to keep it is in its own airtight container, away from anything pungent, and check for softness now and then, since regained moisture is the first sign it needs repackaging.
I used to just dry my cordyceps and jar it like everything else, until I noticed the potency fading faster than expected even in a sealed container. Dried mushroom just doesn’t hold its compounds the way people assume.
If you’d rather skip the trial and error altogether, the Cordyceps Mushroom Tincture is already dual-extracted and stabilized using the spagyric method, so you’re getting the full potency without guessing whether you stored them right or not.
It’s why I keep my culinary mushrooms dried and stored properly on one shelf, and this tincture for lungs and brain support sitting right alongside them, already done right from the start.
09. Vinegar, Pickles, and Anything with a Metal Lid
Home-canned pickles and vinegar-based sauces throw off acidic vapor even through a sealed jar, and given months next to a metal lid, that vapor starts corrosion from the inside before rust ever shows on the outside.
Store acidic ferments with plastic or glass lids where you can, and keep the metal-lidded ones away from the rest of your canned stockpile.
08. High-Fat Foods and the Utility Room
Nuts, seeds, and powdered peanut butter carry enough oil to go rancid fast once heat starts cycling through them, and the generator room or furnace closet is exactly where that cycling happens.
Some preppers I know use that space for both because it’s out of the way, but the temperature swings there are worse than almost anywhere else in the house. Keep high-fat stock somewhere stable instead, even if it means giving up convenience for shelf life.
07. Salt, Sugar, and Moisture
Both pull water straight out of the air and set into a rock you have to break with the back of a spoon. Store them touching, or next to anything damp, and they harden faster still. Salt has a nastier trick on top of that: set it against your cans and it eats the seams, rusting them from the outside until the seal gives.
Store both airtight and bone dry, with salt kept well away from any metal, and drop a few grains of rice in the container to catch stray moisture before it turns the whole batch solid.
06. Seed Bank and Iodized Salt
Anyone doing both food storage and seed saving tends to shelve them in the same cool, dark space, but iodine vapor off iodized salt can hurt seed viability over time. It’s a slow effect, not something you’ll notice until germination rates drop a season or two later.
Store your seed bank away from the salt, ideally in its own sealed container with a desiccant packet, and use non-iodized salt for anything you’re keeping near the seeds.
Actually, the best way to preserve seeds long term is to store them the way Nicole did. Double-sealed bags, with a silica gel pack tucked into each envelope. Store them anywhere after that, next to anything, and they’ll stay protected for 5+ years, depending on the seed type.
Not sure your current storage is doing the job? Test it with the baggy method to check if moisture’s already gotten in.
05. Garden Harvest and Your Sealed Reserves
Anything freshly picked is still breathing out moisture and ethylene, and it usually carries a few insects along with it. Park a crate of garden vegetables against your sealed buckets of rice and beans and you’ve aimed all of that at the supplies meant to outlast everything else.
Keep a real gap between the two, with fresh harvest processed or eaten near the kitchen instead of parked next to the reserves.
04. Freeze-Dried and Dehydrated Foods Near Anything Damp
These are the most moisture-sensitive items in most stockpiles, packed with oxygen absorbers or desiccant specifically because trace moisture is what turns a twenty-five-year product into a two-year one. Store them near a sweating can or a damp basement wall and moisture finds its way past the seal over months, not days.
The best strategy is to store freeze-dried and dehydrated stock on its own shelf, off the concrete floor, in the driest corner you have, and check the oxygen absorber indicator once or twice a year rather than trusting the date on the label alone.
03. New Stock Stacked on Old Stock
Rotation dies the second a fresh case gets shoved to the back instead of the front, and we’ve all done it, tired, arms full, easier to just set it down wherever it fits. Worse, if that new bag ends up pressed right against an older one, any pests already living in the old stock get a straight path into the new.
So separate by date, not just by type, and write the month you sealed it on the front of the container. Future you, digging through the shelf at 2am during a storm, will actually thank you for it.
02. Grains, Flour, and the Pests They Carry
Weevils and moths lay eggs in grain before it ever reaches your shelf, too small to see until they hatch. By the time webbing shows up in the flour or beetles turn up near the rim, the whole batch is usually compromised.
That’s why new grain and flour need three or four days in the freezer first, long enough to kill any eggs already inside. From there, airtight food-grade buckets with a couple of bay leaves or a bit of diatomaceous earth keep things sealed.
Whole grains can hold up for years under these conditions, though flour is thirstier for oxygen and starts losing quality after twelve to eighteen months even when properly sealed, which is where mylar bags with oxygen absorbers earn their keep.
Cardboard and thin plastic won’t cut it either, since moths chew through both without much effort, and a single female only needs a pinhole to lay a few hundred eggs.
The daily-use bucket also deserves its own space, kept apart from reserve stock, so a problem in today’s flour never spreads to next year’s. A quick check every couple of weeks, looking for clumping or an off smell, catches trouble before it spreads.
01. Food and Fuel
The garage is where the trouble usually starts. People push part of the stockpile out there to free up kitchen space, right alongside the gas can, weed killer, and pool shock, and fumes from all three work their way into anything with porous packaging.
Flour, rice, pasta, and beans sitting in paper or thin plastic will pick up the smell and the chemical residue long before anyone notices.
A few pairings are worse than others:
- Calcium hypochlorite (pool shock) near fuel – a strong oxidizer that can ignite on contact with gasoline or diesel vapors. This is a fire waiting on a reason, not just a bad smell.
- Gasoline or propane near dry goods – vapors soak into flour, sugar, and grains stored in anything short of airtight, food-grade containers.
- Herbicides and pesticides near canned goods – residue settles on can lids and lingers on anything handled afterward, even if the seal holds.
Food and chemicals need separate rooms if the space allows it. Where that’s not possible, a hard wall between the two zones, plus sealed metal or food-grade plastic containers on the food side
Special mention: Canned Goods and Where You Stack Them
I’ve been going through the Bug-In Guide again the other day, and the canned goods section is the one that actually opened my eyes. Turns out a can isn’t the sealed vault everyone treats it as. It’s a thin metal wall reacting to everything around it every day, and where you stack it matters almost as much as what’s inside.
Bare concrete or a damp wall makes cans sweat, then rust, and a rusted seam eventually lets air and bacteria in, long before the label gives you any warning. Also, heat does its own damage in the background too, roughly halving shelf life for every ten degrees the room warms up. Up off the floor on wood or wire, cool and dry, oldest cans pulled to the front, that’s what actually keeps them good.
A Navy Seal’s Bug-In Guide goes room by room with real thresholds for temperature and humidity instead of the guesswork most of us are running on.
Wait, you don’t have the book yet? Honestly, you need to get it ASAP. If you’ve got a stockpile you’re proud of, this is the part that decides whether it’s still good in five years or just taking up shelf space.
You may also like:
DIY Plastic Barrel Root Cellar (VIDEO)
Foods You Should Never Wash
10 Ways to Freeze-Dry Your Food at Home for 10+ Years Shelf Life
How to Repurpose Expired Food Cans
27 Foods You Can Stockpile Without Oxygen Absorbers
Read the full article here
