Growing Potatoes in Tires

I was listening to my friends over at Wiggly Wigglers last night. (Note: We’ve never met, but I’ve gone to bed with Heather, Ricardo, and Phil a couple of times a week for months. Very pleasant people. A bit crowded.)

Anyway, they were talking about growing potatoes in tires (or as they like to say: “tyres”). It got me to thinking about my gut reaction that doing so would be a Bad Idea. It would seem to me that tires are made from petroleum and god-knows-what-all. Growing my food surrounded by a wall of degrading car leftovers just doesn’t feel very nature-y.

So, I decided to do a little poking around to see if the issue’s been settled by something more scientific than my distaste for automobiles. I thought I’d make a few notes of my findings for anyone interested.

It turns out that there have been several studies performed on the leaching of tires when used as “light fill.” That pretty much means covering roadways or otherwise grinding them up and using their non-biodegradability (thank you, vulcanization) as an advantage. They’re light, durable, and there are heaps and heaps (literally, billions) of them just lying around starting on fire and serving as mosquito breeding grounds.

I’ve got bad news. The results go something like this. If you’re responsible for dealing with great piles of tires and have an application for which you’d like to use them, you find that they are more inert than about anything assuming neutralish pH. If, on the other hand, you just don’t like the sound of the whole thing, you do your own testing and find heavy metals (a whole salad bar of arsenic, zinc, and lead), oils, and some sweet, tasty hormone disruptors (namely, octylphenol).

Hm. That didn’t help much, did it?

OK, well, here’s my take. Given the uncertainty and seemingly obvious dangers of using something like a tire to grow food… why do it? Is it really that convenient? I recall reading once that the reason everyone gets so religious about their potato growing method is because you basically can’t screw it up. Plant them however you want. You’re going to get potatoes.

I’d just as soon err on the side of safety in this case. For one thing, I don’t want to go to all the trouble to grow my own organic vegetables only to do so in a container never intended to be used for food production and thus made with no concern for that purpose. Secondly, I don’t think I’d feel good about seeing several stacks of tires in my garden.

So, here’s what I’m doing this year:

I bought a $10 or so roll of chicken wire and jammed a couple pieces of rebar in the corners. Every few days I toss some straw and compost in there as the tops grow out. I try to leave several inches of growing top exposed.  No prettier than a tire, I guess.

My other potato patches (I grow a lot of potatoes) are either this way or just trenches that I’m hilling with the compost and straw.

Honestly, I don’t even know that that much work is needed. Last year, I just hilled them up with dirt, and guess what? Lots of potatoes. I’m doing this only because I did find that, using straight soil, things got a bit compacted by harvest time, and we had to do some serious digging to get them out. We missed several pounds of them (as evidenced by them all sprouting this year).

So, there you go. Do I think anyone will die from growing their potatoes in an old tire? Nope. I doubt that, at the levels the stuff leaches out and the rate at which the spuds would have to take it up, you’d be able to tell that they were grown in your old Goodyears. Would I like to see them ground up and used as fill in sensitive wetlands? Not really. Seems like we have much bigger fish to fry, though. Uh, no pun intended.

Personally, I just don’t see the great advantage that offsets the ugliness and potential dangers.

There’s more than one way to grow a spud, you know.