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Wondering what containers people use for growing various edibles. Instead of planting purely outdoors I may grow on the balcony and indoors.

Primary worry is leeching materials/heavy metals/plastics into the soil.

I figure yogurt cups since they are for food.

Those clay pots seem good, but I don't know what they are made of such as any additives that may contain materials that could leech into the soil.

Thanks,

johnnychi
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2 Answers2

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If you are paranoid about this sort of thing, there is probably no answer that will make you happy.

If you are just normally concerned, stick to containers from reputable suppliers that were designed for growing things in. Plastic plant pots are lighter and cheaper to buy than clay, they don't break when you drop them, and they are easy to clean since they are not porous. For larger quantities of vegetables, if you don't need to move the plants about, plant straight into grow-bags instead of using pots.

I wouldn't bother with things like yoghourt pots, except for indoor use. They are too flimsy, they don't have water drain holes, and the UV in sunlight may quickly make them brittle, and unless you buy your yoghourt in "commercial" quantities (e.g. in 5-liter tubs) they will be too small for anything except germinating seedlings.

alephzero
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Plastic is safe (for your plants, not for the oceans): plastic is an organic polymers, so molecules are much larger than roots can absorb, and the elements are usually just normal organic components. The danger for ocean is just the size: too large (also in case of micro plastic) and they tend not to decompose (also in stomach).

But I would check pots for plants (and possibly for vegetables): colours (pigments) may contains some heavy metal (which gives the colour). Plant pots tend to mantain the colour, so they are safe. Other plastic recipients tend to lose colours.

In any case, most of recipients (also clay) should work well. Check that they have natural colours and more traditional forms (the others could have more dangerous materials, especially for "artistic" pots). Choose material that will endure (so less "emission" of material).

Soils contains also metals, and small quantities are not dangerous (in effect we need some of them). I would assume you will not eat only from the plants on your pot, and probably your soil would be much better (more organic, so few metals).

Glasses are also good materials and inert (so glass will not release substances, and on the other hand, glass should not have dangerous elements). Plant on glasses are also nice to see, but you should care that the root will not overheat, and there is not extra greenhouse effect.

Giacomo Catenazzi
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  • Thanks for the response. I dug a bit deeper with the plastics. There are basically two or three plastic types that are safe. Type 2 HDPE Type 4 LDPE Type 5 PP https://www.epicgardening.com/which-plastics-are-safe-for-gardening/ I will see if I can find some glass jars at home for planting. – johnnychi Nov 20 '18 at 05:49