Rain barrel container garden, plastic leaching a concern?

We are using an old plastic rain barrel cut in half as two large growing containers next year. I'm exited about the size giving us companion planting options and optimizing use of the micro climate on the southern face of our house. However, the gick in plastics gives me concern. I've heard before that the blue rain barrels are food grade plastic, the one I plan to use(already cut and filled w/ soil, whoops) is a beige color. does the color have any indication of the type of plastic? Same size barrel as the blue ones they sell everywhere, just beige. Also, I got it second hand from a former neighbor who seemed unclear about what it had held. It smelled faintly of something petroleum based when I cut it in half. Gave it a good scrubbing w/ dish soap and washing soda, wondering if the petroleum smell may have just been the plastic itself. Smelled clean afterward. Thanks For any feed back!

If I didn't use recycled plastic containers of all kinds, I wouldn't have a container garden of any size at all.

What's a concern is something only you can decide for yourself. I gather that Paul Wheaton our gracious host is trying to minimize or perhaps eliminate plastics use throughout his food production/storage/consumption chain. I personally am not.

For me, it's not much of a concern. I have some professional experience with permitting and regulation of soil and water remediation projects, and what science I have picked up tells me that container-grade plastics are a mix of inert stuff and volatiles (sometimes called "plasticisers" since they are what makes plastics literally "plastic" -- which is to say, soft enough to be shaped and flexible enough not to shatter when stressed or hit).

The volatiles are, what can I say, volatile. They are constantly oozing, seeping, or out-gassing from every plastic (a few exceptions may exist, but not among the cheap stuff used in bulk for containers in our society).

But, because they are volatile, they either dissipate into the atmosphere, dissolve in a handy nearby solvent like the liquid in your plastic pickle jar, or break down into more inert compounds. None of this is great if it happens near your food, but the thing to remember is that quantities are very very small; this out-gassing and such does not happen readily or easily, but very slowly over time.

If you're storing your food in these containers, the plasticisers or their breakdown products will be present at some very low level in your food. However they aren't "very" toxic in the amounts at issue. Only you can decide how much comfort that gives you; it's enough for me.

If you're growing plants in these containers, there's an extra set of weathering reactions and bioremediation happening automatically. The stuff leaching from the plastic gets worked on by the oxygen in your garden air, by the water in your pots, by the bacteria and fungus in your soil, and then what survives all that would have to get taken up by the roots of your plants and stored in the cells of your vegetables. These tend not to be very bio-reactive chemicals, and so to the extent this happens at all, it's at parts per million or parts per billion.

Every risk avoided in this life comes at a cost, and there are risks associated with those costs too. If you are a billionaire, sure, you can use hand-coopered wooden vessels for everything and there's no risk that the money you spend will turn out to be something you needed at the hospital when your spleen unexpectedly explodes. But if you're poor like most of us, or even just well-off, you have to measure the opportunity cost of the money you spend minimizing small risks. There's no such thing as zero risk, just "how small can I make it" and "how much money can I afford to spend trying to eliminate ever-tinier quanta of risks?"

I think food grade is better than non-food-grade, but only in the sense that some bureaucrat has looked at what leaches out and said it's probably harmless. Color I don't think is a reliable guide. But I do grow food in black plastic drum halves that used to contain petrochemicals. I wash them and I use them. It's that or don't grow the food for me; there aren't *any* large non-plastic containers out there that I can afford to buy. And remember, it's not a choice between okra-grown-in-plastic and not eating; I'm gonna eat. So it's a choice between okra-grown-in-recycled-plastic and grocery-store-food-grown-with-pesticides-and-chemical fertilizers. Which is riskier? I'm content with my conclusion that the grocery store stuff is riskier. And so I move on.

Dan Boone wrote:What's a concern is something only you can decide for yourself (...)There's no such thing as zero risk, just "how small can I make it" and "how much money can I afford to spend trying to eliminate ever-tinier quanta of risks? (...) I'm content with my conclusion that the grocery store stuff is riskier

Great post Dan! That's pretty much how I operate.

Wow, I second that Leila, thanks Dan. Full disclosure, I was pretty much set on the idea anyway, just looking for some opinions or info. I feel the trade off of my food grown in plastics w/out chemicals & whatever packaging processes is probably hands down the winner over half the gunk in the grocery store. Thanks again.

Dan Boone wrote:I'm content with my conclusion that the grocery store stuff is riskier. And so I move on.

Re-reading this the next day, I realize that while I'm talking risk management philosophy, I should mention that I *also* eat a lot of food from the grocery store grown with pesticides and chemical fertilizer. Poverty sucks, I'm still new at this gardening thing, and once again in my estimation it boils down to "what is the risk compared to the alternatives available to me?"

I'm convinced home-grown the permies way (or what my mom would have called "organically grown" even though I hate that terminology, never having encountered even one ounce of inorganic food) is much safer (and tastier) than supermarket chem-food. But supermarket chem-food is much safer and tastier than no food at all, right? Short of starving to death, it's a constant set of trade-offs between how much you spend versus how much risk you eliminate, and most of us make that choice while sharply constrained in how much we can spend.

Around here good and fresh "organic" food is hard to find and very expensive. I will rarely buy it, because in my judgment the risk from chem-food is kinda low and sorta long-term, while the risks from overspending are (by comparison) sharp and imminent. Bill Gates presumably puts his finger down a lot closer to "organics" on the balance beam because spending ten bucks on a cabbage isn't risky for him. Opportunity cost matters too; if I buy the 10-dollar cabbage, maybe I don't have the money for an eight-dollar tool at a garage sale that will help me grow a healthy crop next year.

I mention this because (unlike my perception of the risk from growing in plastic tubs) the risk of eating chem-food is IMO significant rather than negligible. The treadmill of trade-offs doesn't stop just because the stakes went up. In life we can never afford to stop weighing the cost of our risk-reduction measures. We can never stop going "if I do X action or spend X dollars to evade Y risk, how much risk of Z am I creating in my life and is Z bigger than Y?"

I used to hate plastic. It got thrown away and sat in a landfill FOREVER.

Then I realize I was hating the wrong half of the problem--I should have been hating DISPOSABLE.

I will gladly re-use a plastic barrel or anything else to keep it out of the waste stream and save me money. My mushroom business relies on taking advantage of waste streams for growing media and supplies.

I am a firm believer in reuse it until it is worn out. I pay for the plastic or glass or other material my purchases come it, so I feel the need to use those packages in some way. Glass jars get reused to store rice/noodles/beans/seeds in etc. Empty space in the frig gets filled with a bottle of water. Plastic yogurt containers become plant pots, one with holes for drainage inside another to contain the water. I felt a bit odd to begin with, people gave me those strange looks, but once I mention that I paid for that packaging, and don't have a good reason to recycle it until it gets used a bit more...Plastic Plant pots are great for the change of seasons to transport plants inside or under cover when needed. I have lost many because they dry out quicker, but started putting them close together to retain moisture and heat better.

I'm with Dan on this. Practicalities matter. And yeah, keeping stuff out of the waste stream is good too. I've grown stuff in those polystyrene boxes you get refrigerated stuff delivered in sometimes. I've used a whole bunch of plastic pots I acquired from family/friends. (Though they wear out eventually... having said that I've just realised that the pot I'm thinking of I've been using for over 10 years now so that's not a bad lifetime for thin plastic ). I've grown in a pair of old boots. I've seen an awesome container garden made from half-tyres hung on a wall. (Like the boots, though, watering is an issue as there's not much soil in there.) I reckon using what you've got is the best bet.

Great reply Dan! Btw, I also use "blue" plastic barrels but always with BPA free!

Barrels that are HDPE are the most stable to use for us. They'll be recycle symbol #2.
If you cut the top lip off the barrel it will slide down inside the bottom half and you'll get a super easy self watering planter with a bit of wicking cloth.

Two other points: first plastic barrels are ugly and who wants an ugly garden? Second, here in Australia most people who start gardening do build or buy something to surround the bed and then fill it with bought soil. I understand that insofar as the soil is often so bad, however it is gardening in a big pot with all the problems attached to it: high temperature fluctuations, more need to water, akward working with all the edges to work aroud. In case you are renting, or you don't want a bed so close to the house (yes it's not good for the house) then go for it otherwise I would do a normal garden bed.

We just built a couple of these. The cost was nominal.

Angelika Maier wrote:Two other points: first plastic barrels are ugly and who wants an ugly garden?

A hungry person?

You're not wrong, there are ways to address the aesthetics of a container garden assembled from random scrounged plastic containers but in general it's extra work without which things will look a bit junky.  But if you've got the conditions that make a container garden necessary or useful, it may be better to have one than to have no garden (or a less successful/productive garden) at all.  

I find that over time I am transitioning away from thinner/smaller plastic containers toward thicker/larger ones, and away from plastic toward harder-to-scrounge containers made of metal (galvanized steel, stainless steel, enameled steel, and aluminum).  I'm also transitioning my gardening toward raised beds (as I can build and fill them) and open-to-the-ground raised planters (mostly made from tires).  But the pressures that got me started container gardening have not eased at all.  By far the biggest is the nibbler pressure at ground level and below, with the greater attention I can pay to weeding and watering pots at waist level a close second.

Jim Bryant - I like your raised garden idea!

My understanding is that most of the BPA leaching issues have been with hot liquids: baby bottles, coffee cups, food being microwaved in plastic containers, etc.

I'm not overly concerned about my rain barrel reaching temperatures where that would become an issue, especially since I don't drink it directly. For me, the benefits of having a sturdy yet lightweight container, and most of all an existing one (it came with the house) beats any theoretical concerns I may have.

Roy Hinkley wrote:Barrels that are HDPE are the most stable to use for us. They'll be recycle symbol #2.
If you cut the top lip off the barrel it will slide down inside the bottom half and you'll get a super easy self watering planter with a bit of wicking cloth.

If you're still around, Roy Hinkley, please explain a bit more about how this would work (or anyone who can explain -- thank you).  I'm all for self-watering, mostly because I live in an arid area and self-watering has got to be less wasteful of water than top-watering.  Or maybe there's a permie forum just about constructing self-watering containers.  I'll look for that, too.