RE: Mini/Barrel Root Cellar - Questions about materials.

Hello! First time poster on this forum.

I am looking into installing a small root cellar on my property sometime in 2024. The plan right now on using a 55 gallon barrel as the actual "body" of the cellar, and to have the entire barrel except for the first couple inches buried int he ground.

I had a couple questions that I thought some people here might be able to answer, mostly regarding materials.

1.  Would it be better to use a plastic barrel, or a steel barrel as my cellar? Is there any advantage to using one material over the other?

2. If I were to use a steel barrel, should I expect it to corrode and rust away in a few years, or should they last for a long time? I believe most 55 gallon steel barrels are galvanized.

Thank you!

Hello Ryan, Welcome to Permies!
Making a root cellar sounds like a good project to extend the life of our produce - do you know what you are likely to be storing? I suspect the advantages and disadvantages of the barrel material may be a bit climate/soil dependent. So (not speaking from experience!) here goes:

Plastic barrels will be waterproof, insulative (both thermally and electrically) and durable. They will be able to take small earth movements and withstand small amounts of pressure changes. They will be easy to clean and don't need painting or other treatment to extend their life. On the down side they will (eventually) degrade to microplastics unless recycled. Having an outside life means that successful recycling is less viable. They can contain or absorb toxins to an unknown extent so I would try and get one that has had food use previously. Vermin have been known to chew through plastic and indeed find some plastic irresistable. The surface will probably scratch and be less easy to clean as it is used.

Metal barrels will be waterproof, conductive (both thermally and electrically) and durable. They can take larger earth movements and withstand greater pressures than a plastic barrel. Assuming a mild steel barrel (stainless would be lovely but much more expensive!) it will need surface treatment to protect against corrosion in a moist environment - either paint or zinc are the most common treatments, both can have negative environmental consequences. Zinc in particular, although giving the best protection, I believe to be toxic in aquatic environments. Metal will eventually corrode and may become less easy to clean, but will be more vermin resistant overall.

I think cleaning out the cellar and emptying it in use may be awkward to do in a vertically buried barrel, and would be interested to hear other peoples' thoughts on those aspects.

While I am do not know much about barrel based root cellars, this reminded me of other Permies post that might give you some ideas.

https://permies.com/t/225152/gal-barrel-buried-testing-food

I hope it might inspire you.

Hi Ryan;
A long story for a short answer...

In 1992 I built my auto shop.
I planned on installing an inground hoist, I even traded some auto work for a used one.
I acquired 3 metal 55-gallon barrels. I removed the top and bottom from two and welded all three together.
I buried the whole thing in the center of my then-dirt shop floor.
Then after all that, I never installed the floor lift... I placed an old stop sign over the barrels and ignored them for many years.

Some years back I dabbled with making cheese.
I quickly realized that my refrigerator was A) not large enough and B) not the proper temps and humidity for aging cheese.

I "remembered" my nine-foot-deep hole in the shop floor.
It was in perfect condition after 20-plus years!  The temperature remains in the 50s and humidity runs around 70%
I used a styrofoam cooler to raise and lower the cheeses for aging, it worked perfectly.

I no longer make cheese, but it is now almost 2024 and my metal barrel storage area is 32 years old with no deterioration at all.
Admittedly, it is under a roof so no moisture can get to it.

I vote for using metal.