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Choose Safe Containers for Growing Food

While not wanting to dampen your enthusiasm for gardening in repurposed planters, I encourage you to do your due diligence when choosing that perfect container.

Once a computer terminal relegated to the scrap heap when some fancy, flat-screen newcomer came on the scene.  Now, it’s been transformed into a funky planter.

Recognise this? It was once a computer terminal relegated to the scrap heap when some fancy, flat-screen newcomer came on the scene. Now, it’s been transformed by an innovative gardener into a funky planter.

The majority of pre-loved or second-hand goods will be safe to use, but before you reuse a container for planting in, here are some considerations other than whether it can hold some dirt and leafy greens!

My philosophy is “to err on the side of caution – it’s better to be safe than sorry!”

  • Check the Skin it’s In!  What is the container is made of? If you can, find out what material the container or item is made from (especially on the surface).  Is it safe?  Is the surface porous?  Some materials such as terracotta are extremely porous and can absorb and leach water soluble chemicals through the surface.
  • Avoid Materials contaminated with Lead or Asbestos:Lead is a naturally occurring metal but it is also a very toxic poison to all forms of life.  Soil can become contaminated with lead if it comes in contact with lead based paint.  Try to avoid choosing items to repurpose into a planter that may contain lead and asbestos such as old containers coated with lead based paint or building materials that may contain asbestos.  Prior to 1970 paints contained high lead concentrations and prior to 1950, some paints had as much as 50% lead in them. However today the maximum recommended amount allowed in domestic paints is 0.1%.  The danger with leaded paints is when the paint deteriorates (by peeling, chalking or turning into a fine dust).

 

When reusing a container, it's wise to check whether the surface contains harmful substances like lead.  Photo by Kevin Rosseel.

Peeling or cracking lead-based paint on an old container is a hazard to watch out for.

The most common areas lead based paint was used in homes is on interior and exterior walls, cupboards, skirting boards, window frames and doors, gutters, fascias, metal surfaces and areas with enamel paint.  If you want to reuse an item such as an old window frame, it’s important to check the age of the house it came from to make sure you avoid paint contaminated with lead.

Check the age of the recycled material you may be using as a planter especially if it's sourced from a house demolition.

If you are renovating or sourcing materials from a salvage shop, recycling centre or second-hand building supplier, it is wise to find out the age of the materials first. Be cautious about reusing painted materials for a garden planter if you can’t determine they’re safe – reuse them in a potting bench instead!

 

  • Past life:  Do you know the history of the item?  If you are salvaging it from a farm or garage sale, has it had contact with agricultural chemicals like herbicides, fungicides and pesticides?  Or has it held other toxic chemicals or dangerous substances (e.g. from medical or industrial sources, drugs or poisons)?  If so, it would likely not be safe to plant into and especially not for food.  Many people reuse plastic buckets as containers to grow food gardens – if they’ve come from the food industry (and are food grade plastic) this is fine but if they have come from a factory manufacturing polymers or other chemicals, perhaps it would be wise to find another planter.  Pay particular attention to the recycle numbers on the plastic container – avoid plastics numbered 3, 6 and 7.

 

Look out for a small triangular recycling symbol usually on the base of plastic materials.

You can check whether a plastic container is safe for use in your garden by looking for the recycling symbol. It’s usually on the base.

 

  • Still not sure? Read the comments on this page or use the search box for further discussions on a wide range of materials. You can also look for the relevant MSDS (Material Safety Data Sheet) – this site provides free MSDS information and is one source you can check. You can find out more about specific materials such as terracotta, concrete and plastic in Choosing A Container – the Pros and Cons or leave a comment and I’ll try and check it out for you.

 

Containers suitable for use as planters are made from all sorts of materials - each with pros and cons!

Containers suitable for use as planters are made from all sorts of materials – each with pros and cons!

 

No matter how appealing the container looks, please consider carefully whether it could leach residues into the soil before planting directly into it.

If you have found the perfect planter but still have concerns over whether it’s safe to plant in, here’s an easy solution.

With a little creative thinking, you may be able to still use it as a ‘Cachepot’ – an outer decorative or ornamental container used to conceal a smaller pot plant. Cachepot comes from the French word cacher, to hide + pot, pot.

This technique is also known as double potting.  You simply put your plant into a safer small pot inside your cachepot. Cachepots allow you to use containers that are visually appealing, without worrying about whether they are leaching toxic chemicals into your food.

 

A timber barrel treated with a preservative stain looks attractive on the outside, with a plastic pot of edibles inside.

A timber barrel treated with a preservative stain looks attractive on the OUTSIDE. Edibles are planted in a less attractive, but safer plastic pot INSIDE.

 

Nestle the plant pot down inside the cachepot or outer container. If you want to, cover the top of both containers with mulch so you can’t see the inner pot.  No one will ever know!

Interested in this topic?  There’ll be more specific information about the dangers lurking in our gardens in a future post so if you don’t want to miss it, subscribe to my newsletter (and grab your free eBook) or click on the RSS feed below or to the right.

Want to learn more?  Check out Container Gardening and Growing Your Own Food.

© Copyright Anne Gibson, The Micro Gardener 2010-2013 – http://www.themicrogardener.com. All rights reserved.

72 responses so far

72 Responses to “Choose Safe Containers for Growing Food”

  1. Sarah McCarronon 01 Sep 2011 at 12:08 pm

    Hello!
    This is such wonderful information. I am starting a container vegetable garden for the first time, I am a beginner gardener. I found some old drawers on the side of the road. They are mostly fiberboard, not real wood. Would these be safe to grow veggies in? I see lots of blogs, articles, and photos of people who’ve grown vegetables in old drawers, but my concern is that the fiberboard is treated with chemicals and/or that it could rot.

    Thanks
    Sarah

  2. The Micro Gardeneron 01 Sep 2011 at 1:31 pm

    Hi Sarah

    Thanks for your feedback on this article and glad the information is useful to help people question rather than assume, that a container is safe. Unfortunately we have to take responsibility for our own health, and even more so, when we are choosing to grow our own food organically.

    Regarding your drawers, whilst I am not a trained expert in this area, I read academic and government papers regularly and try to do quality research to give me a better understanding of what some of the issues can be around certain types of materials, and at least know whether to be cautious or seriously concerned. Fibreboard (which is also known as MDF or medium-density fibreboard) would most likely fall into the ‘unsafe’ category as far as I’m concerned. From some initial research here are a few points to be aware of:

    “Formaldehyde resins are commonly used to bind MDF together, and testing has consistently revealed that MDF products emit urea-formaldehyde and other volatile organic compounds that pose health risks at sufficient concentrations, for at least several months after manufacture.[4][5][6] Urea-formaldehyde is always being slowly released from the surface of MDF. When painting, it is good idea to coat the whole of the product in order to seal in the urea-formaldehyde. Wax and oil finishes may be used as finishes but they are less effective at sealing in the urea-formaldehyde.[2] – Ref: http://en.wikipedia.org/wiki/Medium-density_fibreboard

    With regard to health risks:

    “In all fibreboards, formaldehyde resins are used to bond together the constituent parts. This is usually urea formaldehyde, but some fibreboard including exterior or marine quality board will use stronger glues such as phenol formaldehyde. Even at a low level, exposure to formaldehyde though inhalation can cause irritation to the eyes, nose, throat and mucous membrane. Formaldehyde can also affect the skin, leading to dermatitis, and the respiratory system causing asthma and rhinitis. The International Agency for Research on Cancer (IARC), part of the World Health Organisation, quoted evidence that even short term exposure to formaldehyde, at far below the legal limit allowable in Britain, could cause irritation to the eyes, nose and throat. The IARC’s findings also stated that wood dust is a carcinogen’ (cancer causing) and that ‘formaldehyde is probably carcinogenic to humans’. IARC was also concerned about the reproductive hazards of formaldehyde’. Formaldehyde is classified in the UK and throughout Europe as a Category 3 Carcinogen. This means it is a substance which “causes concern for humans owing to possible carcinogenic effects but, in respect of which, available information is not adequate for making a satisfactory assessment.” This puts formaldehyde on the GPMU list of potential carcinogens, meaning it should be replaced where possible, and if not, subject to rigorous controls that reduce exposure to the lowest possible level.” – Ref: http://www.childrensfurniture.co.uk/mdf.html

    So, without going on further, I guess you have to find out IF the drawers are made from this material, and then decide what state they are in and whether you want to keep them or use a safer alternative. It may be possible to paint them – but perhaps consider using an eco-friendly low-toxic paint! You can also refer to some of the articles on this site about repurposing containers. If you are able to satisfy yourself the drawers are not going to continue emitting toxic VOCs which could be harmful to your health, and you are really in love with this piece of furniture and still want to use it to grow food, I would still err on the side of caution and perhaps use a safe cache-pot container to grow your food and sit this inside the drawers.

    I hope this helps in doing your due diligence. Feel free to ask more questions if you need to! Otherwise Sarah, I hope you enjoy learning how to grow food at home and can pick up some tips here – feel free to email any time if you need help. If you subscribe to my newsletter, you’ll get all new articles plus lots of tips and a free eBook I wrote which is designed to help beginner gardeners.

    Look forward to staying in touch and would love to know how you go with your drawers!
    Happy gardening, Anne

  3. Sarah McCarronon 01 Sep 2011 at 2:47 pm

    Wow! So grateful for your thorough response. So much helpful information. Very much appreciated! Excited to continue learning.
    All best to you.

  4. The Micro Gardeneron 01 Sep 2011 at 5:15 pm

    My pleasure Sarah. I’m working on some more posts on safe gardening so watch this space!
    Cheers,
    Anne

  5. […] Effel (that’s Steve’s spelling. Ethel is his girl and so he can spell her name however he sees fit!) Doocark has now been given 7 eggs to sit on. She has steadfastly refused to allow the fact that she has no eggs to stop her from returning to her nest each and every morning as soon as we let her out of the coop and she has to be picked up by Steve each evening and returned, protesting, to the coop at the end of the day. We have decided that the other chook who has no name and who has hidden herself away somewhere is going to most probably have some babies one day, so it’s only fair if Effel has a go as well. We have given her 7 fresh eggs to sit on. We have learned a lot about eggs. The only real thing is that they need to be somewhat fresh, and they need to be all put under the chook at the same time as that is what starts the embryo forming. We are hoping that she doesn’t get scoffed in the night because we have a soft spot for Effel. She is the only one of our chooks that is somewhat tame and who will take food from our hands. She may have been hand raised in the past. Who knows? All we know is that Effel is getting her chance to be a mum. We have 3 broodies, 4 mums, 5 regular non-broody hens and Big Yin who is fussing about them all. We have gone from complete and utter novices with anything to do with poultry to being thrown in at the deep end and forced to learn, researching sometimes late at night to find out how to sort problems out, work out what to do with broody chooks etc. It’s a real learning curve but I love researching and finding things out. I am “dead chuffed” by the way. Welcome to Annie from a most amazing blog “The Micro Gardener”.  I used one of Annie’s lovely pictures in a previous post (the lovely boots full of plants) and I urge all of you to head over to Annie’s blog and have a gander. You will be stuck there for hours it’s that interesting and informative. If you are clever (I am ) you will sign up to follow her blog and you will get an amazing free e-book that is cram packed full of fantastic information. Annie, like me, loves to research things and find things out. I consider you a kindred spirit Annie and am so pleased that you have decided to follow my humble little blog. http://themicrogardener.com/choose-safe-containers-for-growing-food/ […]

  6. narf7on 16 Nov 2011 at 4:50 pm

    Err hopefully you put that there Annie…I have no idea how it got there if you didn’t because I most certainly didnt! Feel free to delete it if its not something that you put there :o)

  7. The Micro Gardeneron 16 Nov 2011 at 5:15 pm

    Thanks Fran for the lovely feedback … will be watching your journey with interest! You’ve got a lot going on there. We can all learn from each other. It’s amazing how many life lessons come from our backyards!

  8. Ermelindaon 16 Nov 2012 at 5:03 am

    Great information. Lucky me I came across your website by chance (stumbleupon).

    I have book-marked it for later!

  9. Chrison 30 Nov 2012 at 7:10 am

    Hi, I’m trying to get a container herb garden going, as a sort of trial to see if I could do it then I’d add some veggies too. However, as I’m a prep cook and our restaurant goes through large cans of veggies on a regular basis, I was thinking about salvaging some of them to use for my herbs and maybe later some veggies. However, I can’t seem to find any info on if they’d be safe for food gardening! Any thoughts? Some logic would say that if they’re safe enough to can food in, they’re safe enough to grow it too, but I don’t trust it enough to buy into it fully yet! Again, any thoughts would be appreciated!

  10. The Micro Gardeneron 30 Nov 2012 at 11:16 am

    Hi Chris

    Great to hear from you and a thought provoking question. My philosophy with growing food in repurposed containers is to err on the side of caution and do your due diligence. This is a HUGE topic and one I’ve had an interest in for several years. I have accumulated a lot of information on it but haven’t had the time to put together a book yet. The short answer is don’t assume canned food is safe to eat!

    Here’s some recent research from an incredibly reliable source EWG who do an amazing job on behalf of consumers to find the truth and expose it on all sorts of food and personal products. Their website is a wonderful source of information and is worth a good walk around to familiarise yourself with some of the dangers associated with everyday purchases. Here’s a very brief summary of their findings:

    “Independent laboratory tests found a toxic food-can lining ingredient associated with birth defects of the male and female reproductive systems in over half of 97 cans of name-brand fruit, vegetables, soda, and other commonly eaten canned goods. The study was spearheaded by the Environmental Working Group (EWG) and targeted the chemical bisphenol A (BPA), a plastic and resin ingredient used to line metal food and drink cans. There are no government safety standards limiting the amount of BPA in canned food.” There is a wealth of information on BPA out there for further reading.

    Obviously metal cans rust quite quickly when they come in contact with moisture but lining them with plastic to lengthen the life of the can as a planter then brings into question how safe is the plastic? There are alternatives such as coir peat (a sustainable resource) that would act as a natural barrier but I haven’t read any findings on leaching of chemicals through a lined can. I use metal cans as planters for non-edible flowers that bring pollinators to my garden so I AM reusing them, but not for food. When their usefulness is up, then I know I’ve done my best to repurpose the material and not just add to landfill.

    More research on this topic is definitely needed. If you find any answers or reports that help shed light please feel free to share them here to inform others. I will also update this website as I find out anything new. Hope this helps somewhat! :)

  11. beverly alexanderon 08 Mar 2013 at 4:41 am

    I purchased containers in the US but were made in Canada. The bottom of the planters say D81614. Wondering if these are safe for gardening vegetables. Thank you.

  12. The Micro Gardeneron 08 Mar 2013 at 6:39 am

    Hi Beverly
    I can’t say for sure as I’m not familiar with that numbering system. Perhaps you could start with the retail outlet and ask if they can provide you with the supplier or manufacturer’s name. Once you have that, you can ask for specifics. If I have any concerns about a material or have not been able to ascertain the history/source, I add zeolite to the potting mix or garden bed. Zeolite is a natural mineral that helps bind toxins and contaminants in the soil. Hope this helps! :)

  13. Kateon 20 Mar 2013 at 12:51 pm

    Hi Anne,
    I’m looking at repurposing an old Weber BBQ as a mobile herb pot. It was only after i painted the weber that I now worry whether it will be unsafe to use for veggies or herbs – because of the paint. Would you know whether spray paint would be toxic to grow things in? Thank you

  14. The Micro Gardeneron 20 Mar 2013 at 2:52 pm

    Hi Kate
    Thanks for your inquiry and great to hear you are repurposing a Weber BBQ! A mobile herb pot is a fantastic idea. I can’t really comment on your particular situation in terms of the kind of paint you’ve used. If you are worried it is chemical based, then perhaps you could contact the manufacturer and explain the application you are wanting to use it for and ask if they can provide you with a MSDS (Material Safety Data Sheet) on their product. If you think it could potentially leach chemicals into the soil, then I’d suggest a) either giving it a coat of non-toxic paint over the top of what you’ve already done b) adding zeolite (a natural mineral you can buy in small quantities from produce stores) to the soil. It helps bind toxic substances and make them inert so this could be an ‘insurance policy’ of sorts! Hope this helps. Please feel free to share your pic on The Micro Gardener Facebook Page or email me if you’re happy to, when you’re done. I’m sure your project would inspire others. Hope this helps. :)

  15. Kateon 20 Mar 2013 at 6:44 pm

    Thanks so much for the great advice, Anne! Will send a pic through when it’s done.

  16. Lynnon 09 Apr 2013 at 9:46 am

    Hi Anne, I found 24″ Fiskers plastic, clay colored pots in a big box store. The only numberon the bottom is 24, assume that it refers to the diameter. How do I know if these are safe for growing edibles? I’ve checked the Fiskers website and cannot find any info. Thanks for giving me peace of mind.

    Lynn

  17. The Micro Gardeneron 09 Apr 2013 at 10:57 am

    Lynn I’d suggest contacting Fiskers direct and checking with them about the product you have. They may be able to supply an MSDS (Material Data Safety Sheet) or at least advise which plastic recycle number it is. I recommend avoiding 3, 6 and 7. Perhaps ask the question via https://www.facebook.com/fiskars? Hope this helps.

  18. […] particularly if you’re trying to grow organic produce! So how do you know if it’s safe? The Micro Gardener (who has done quite a bit of research on this topic) recommends you steer clear of plastics 3, 6, […]

  19. Ten Water Saving Tips for Your Garden |on 23 Apr 2013 at 6:43 am

    […] one.  A mini in-situ worm farm I use is the Little Rotter – it’s compact, made from a safe plastic and adds humus where you need it (directly in your […]

  20. Katieon 15 May 2013 at 8:53 am

    Hi Anne, and thank you for the great page! I am thinking of using an old trunk that’s bottom is a bit worn down from getting wet. There is fabric on the inner walls I may pull out. Could I line this with anything to make sure it is safe to grow herbs in? thanks so much for your wisdom!
    Happy growing!
    -Katie

  21. The Micro Gardeneron 16 May 2013 at 6:37 am

    Hi Katie
    Thanks for stopping by. Firstly I’d suggest adding drainage holes in the base so your plants don’t become waterlogged. You don’t mention what the trunk is made of – metal? synthetic? If you know, you could do some research on the type of material to find out if it’s likely to leach any chemicals and whether it’s an issue or not. You may also want to block the moisture from rotting the trunk if water will degrade it. If so, line with something like weed mat you can cut to size which will add a less permeable layer inside but still have drainage on the bottom. Or if you want to preserve the trunk for much longer, why not source another smaller container you DO know is safe to plant into and sit this inside? Then use the trunk as a decorative outer cachepot. I also add zeolite (a natural rock mineral) to the potting soil mix to absorb any toxins that may leach into the growing medium. Zeolite binds the toxic chemicals and renders them inert. It’s kind of a natural insurance policy. Hope this gives you some options to consider. :)

  22. Tinaon 09 Jun 2013 at 11:46 pm

    Hi, I bought some old popcorn tins at a garage sale and I am planning on lining them w tree bark paper before I put my vegetable plants in them. I know they will probably rust, but I figure they are a one season use anyway. Wondering what popcorn tins are made out of and what chemicals might leach into my plants if I use them? I did a google search and found that tins are either aluminum or steel w aluminum paint… Are these safe to plant in? Thanks for your time :)

  23. Tinaon 09 Jun 2013 at 11:52 pm

    Whoops! I meant steel covered w tin paint, not aluminum :)

  24. The Micro Gardeneron 10 Jun 2013 at 8:21 pm

    Hi Tina

    I’m not familiar with popcorn tins but found a company that makes them @ http://www.ballsteeltinusa.com/our-products/popcorn-tins/ – perhaps if this is the style of tin you have purchased, you could contact the company directly to learn more or ask for a MSDS (Material Data Safety Sheet).

    If the metal is stainless steel, it’s worth knowing that it can leach some heavy metals according to research I’ve done. You can read more in the article ‘Stainless Steel Leaching into Food & Beverages‘. Whilst this information doesn’t specifically relate to growing food in stainless steel, one can reasonably conclude that if it leaches heavy metals like nickel, chromium and iron into food, this could also occur in soil. So I guess it’s a matter of applying the ‘precautionary principle’ and erring on the side of safety rather than risk. If I’m unsure about whether there could potentially be toxic substances in my soil or a container, I add zeolite, a natural mineral that helps absorb heavy metals and prevents them from leaching into the environment – a kind of ‘insurance policy’.

    You may also find a comprehensive Review of Stainless Steel Toxicity of interest. It’s my opinion to balance repurposing materials as planters with avoiding unnecessary health risks. You can always use the tins for flowers or other ornamentals rather than food and consider some other materials that are low cost to repurpose. There are plenty of ideas on this site. Hope this helps! :)

  25. […] anything can be a planter if it has drainage, although it’s important to make sure your container is safe for growing food if that’s your intention. My plastic blender jar was on it’s way out, so I ordered a […]

  26. […] that some plastics do break down over time and can potentially leach into the soil… this excellent website talks about what reusable plastic containers are safe, it says to avoid plastics with the number […]

  27. […] that some plastics do break down over time and can potentially leach into the soil… this excellent website talks about what reusable plastic containers are safe, it says to avoid plastics with the number […]

  28. Michelleon 22 Oct 2013 at 5:56 am

    Dear Anne, thank you for your wonderful site, I’m so happy I stumbled upon it.
    A question regarding painting plastic containers: I found some nice big containers from the food industry that I would like to repurpose as planters for edibles. Only thing is they are a rather ugly color… do you know if it would be safe to use acrylic ( or any other type of) paint on the outer sides or could leaching be a problem?

    Thank you!!

    Michelle

  29. The Micro Gardeneron 25 Oct 2013 at 2:36 pm

    Hi Michelle
    Thanks for your question. My first thought is: Are the plastic containers definitely safe to grow food in? Since you are repurposing them from the food industry I am guessing they probably are – but just to make sure, check the recycle numbers first (avoid 3, 6 & 7). Re painting them, I assume you will be painting the outside only but there are eco-paints or non-toxic, no VOC (volatile organic compound) paints you can use. Try Googling the terms “Eco paint” or “environmentally friendly paint” for your location. This would be a good starting point. To keep costs down, you can also ask for sample pots until you are happy the paint is suitable and adheres to the plastic OK. You may have to scour the plastic surface for it to adhere properly or use an undercoat in the same colour. Hope this helps! Would love you to share before and after pics with me to inspire others if you go ahead with your project.

  30. Meredithon 26 Oct 2013 at 8:09 pm

    Hi Anne,
    Great article with some very useful information. Certainly plenty of food for thought! I’m considering building a vertical edible garden using sections of roof guttering. I’d be looking to use more modern guttering (either newish 2nd hand or brand new). This should avoid hopefully avoid the lead paint issue. Do you have any thoughts or comments on how safe it is to grow and eat produce grown in this type of metal gutter containers.
    Many thanks in advance for your advice.
    Meredith

  31. The Micro Gardeneron 26 Oct 2013 at 10:07 pm

    Hi Meredith,

    I haven’t done exhaustive research into this as yet but do have some info which may assist you in making a more informed decision. One report indicates the leaching of heavy metals (including zinc, copper and lead) from (even new) roofing materials contaminated water – particularly from galvanized steel products. Other research shows this result to be consistent. As plants take up water through their roots, they may well be affected by this contamination and many other factors come into play. Zinc is not considered a “food-safe” material and it is recommended to avoid contact between food and galvanized surfaces because acidic foods can dissolve zinc.

    You also need to consider that whilst metals do leach, if you preserve the gutters with some form of chemical paint or other coating, this too may contribute to the problem of food safety. See p1-7 in this research study for the wider implications on human, animal and soil health from metal toxicity.

    See below for other research articles that may be of interest:
    http://www.mgma.co.uk/pdf/mgma_metal_gutter_the_guide.pdf
    http://www.empa.ch/plugin/template/empa/*/78530/—/l=2
    http://nora.nerc.ac.uk/813/1/N000813PP.pdf
    http://www.redbeacon.com/hg/pros-cons-wood-pvc-vinyl-metal-gutters/
    http://www.lead.org.au/q&a/2012/20120306.html
    http://www.ehow.com/info_7794966_metal-collecting-potable-rain-water.html
    http://gardeningwormcomposting.com/is-galvanized-steel-harmful-to-the-soil/
    http://www.finishing.com/71/64.shtml

    In any case, other considerations are that metal gutters will heat up considerably and this may affect a) damage to the root zone particularly as they are so shallow b) the necessity for frequent watering due to the shallow depth c) the need for a high quality planting medium to retain moisture or limited plant choices to suit this situation.

    Ultimately, I urge people to use the Precautionary Principle i.e.err on the side of caution – there are so many safe options, why potentially put your health at risk? Check the vertical gardens section on my site for loads more structures you can use to grow food safely whilst still maximising space. Hope this helps. :)

  32. Michelleon 29 Oct 2013 at 12:46 am

    Dear Anne, Thank you so much for your response and the helpful information. I shall let you know how the project unfolds!
    All the best

    Michelle

  33. […] Artigo sobre como escolher/comprar os seus canteiros: http://themicrogardener.com/choose-safe-containers-for-growing-food/ […]

  34. Skyeon 01 May 2014 at 4:26 am

    Hello…I am considering investing in a raised bed planter made locally here in Colorado…I spoke with the owner of the company today (GrowTrek) and asked if he knew what the plastic liners in the planter are made of…He said they are made from recycled billboards and he was not certain what the material is exactly and if it is toxic…he has grown his own food in these containers for quite some time and has no complaints…I have researched a bit on line but haven’t found any clear answers about the recycled billboards…maybe vinyl of some kind? Do you have any thoughts?
    Thank you so much.

  35. Anne Gibsonon 01 May 2014 at 11:12 am

    Hi Skye, great to hear you are getting a garden going in a raised bed but I think you are right to ask questions about the products you are considering. I believe companies marketing/selling products for growing food should do their due diligence on the materials/manufacturing processes. Consumers have the right to know what safety issues may be associated with a product. We have to take responsibility for getting information on the products we buy and I think it’s important to find out if there are any potential leaching of chemicals issues with recycled vinyl. I would ask what the process is and suggest you follow up with GrowTek and ask for their MSDS (material data safety sheet) which may provide more information. With moulded products, sometimes the manufacturing process renders chemicals inert but when they are recycled this may change the structure or properties. Perhaps also research alternative products that may not have this potential issue? There are many raised garden beds you can make yourself and quite economically such as haybales, which can still look attractive. Here’s one site that discusses the recycling of billboards that may help give you some contacts. http://greenbusinesswatch.org/blog/relan-recycling-and-repurposing-billboard-vinyl. Hope this helps. Would love to hear back on what you find out!

  36. farahon 03 May 2014 at 6:08 am

    Hi .. this great info. Thanks so much. I want to start a herb garden and I have a lot of baby formula containers. Are they safe?

  37. Ulrike Johnstonon 09 May 2014 at 3:31 am

    Should I be concerned about the glue used in wooden planter used for growing food? The wood is untreated cedar and I am happy with that, however, glue is used in the construction.
    Your comments would be appreciated.

  38. Anne Gibsonon 09 May 2014 at 3:20 pm

    Hi Ulrike
    I don’t a definitive answer to this question. All glues have chemicals and based on what I’ve read about many products, sometimes the process used during manufacture can render the chemicals inert (safe). However, over time they can biodegrade and then their properties can change. I’m not an expert in this field. Could you check with the manufacturer of the planter? Perhaps they could send you to a website where there’s more specific information on the product you are using? Depending on the chemicals in the glue, these can be pretty toxic. Here’s an example of one such chemical used as a glue preservative. http://www.epa.gov/ogwdw000/pdfs/factsheets/soc/tech/pentachl.pdf. It’s wise to do your due diligence if you are an organic gardener. Let me know if you find out anything and please share the results here to help others. Good luck.

  39. Anne Gibsonon 09 May 2014 at 3:32 pm

    Farah thanks for your comment. You don’t mention what the containers are made of – plastic? metal? other? I would check with the manufacturer if you’re not sure – ask for an MSDS (Material Safety Data Sheet). This may provide additional information about the packaging of their products. I’m not a fan of growing food in metal containers due to chemicals leaching – there are many safer alternatives. Consider natural materials you can repurpose such as cane baskets which don’t last a long time but are much safer. Hope this helps.

  40. Mimion 17 May 2014 at 4:20 am

    Hi Anne. I have a question about pots and spray painting them. I plan on starting a basil plant, and I have this one terra cotta pot that I would like to spray paint (with Rustoleum brand), but I’m a little hesitant.. My gut is telling me that it’s probably a bad idea, but I’d like to hear your thoughts on this. I’ve so far painted the OUTSIDE of the pot, but held back on painting the inside, at least until I hear back from you. Thank you!

  41. Anne Gibsonon 17 May 2014 at 2:58 pm

    Hi Mimi
    I am not sure WHY you want to spray paint the interior of your terracotta pot. It’s going to be filled with soil and a plant so what is the purpose? Terracotta has many advantages (see my post on Choosing a Container – Pros and Cons) for more information. I recommend avoiding chemicals where food plants are going to be grown and terracotta is a very porous material so moisture moves in/out of the surface. If you really want to change the way a pot looks, you can always consider using a cachepot (larger decorative outer pot with smaller one inside). Hope this helps and gives you some ‘food’ for thought!

  42. Sorenon 17 May 2014 at 10:32 pm

    Hello Anne,

    Thank you for the helpful information and I’d kindly ask your experience about the following: I’m intending to plant vegetables in terracotta pots that are decoratively painted on the outside; and on the interior have either residual splashing of the exterior paint and/or have been painted black.

    The pots were purchased about two years ago from my local garden center for the explicit purpose of planting. Therefore, I assume the paints used are non-toxic, but I don’t know if the pots are explicitly safe for vegetables (I was previously using them for flowers).

    The folks at the garden center had only speculative information. In your experience, if a terracotta pot is painted by the manufacturer on both the interior and/or exterior, is it reasonable to assume the pots and paints safe for vegetables?

    Thanks so much,
    Soren

  43. Mimion 18 May 2014 at 4:53 am

    I wanted to paint the rim and a little further, where the soil would not be touching, not all of the inside.

    So since it is so porous, is it bad to have painted the outside at all? I know it’s on the outside, but would the chemicals from the paint on the outside of the pot somehow make it to the inside of the pot where the soil and plant are located?

  44. Anne Gibsonon 20 May 2014 at 2:36 pm

    Hi Mimi
    I really am not sure about that – due to the porosity of terracotta, I guess some leaching of soluble chemicals is possible and you don’t mention what kind of paint, so I’m guessing it’s not an Eco paint (no VOC). If you want to be sure, why not add a smaller container inside and grow your plant in that if you have your heart set on painting the pot to look nice? Alternatively you can buy ceramic pots (see my post on Choosing Pots – Pros & Cons for more tips). That may be another option for you.

  45. Anne Gibsonon 20 May 2014 at 2:56 pm

    Hi Soren
    I am not sure whether you mean hand-painted terracotta or ceramic (glazed). The processes are quite different. Check out my post on Choosing Pots – Pros & Cons for more information including the comments section. You may also like to read my replies to Mimi’s similar question in the comments on this page. You could try asking your garden centre for the name of the manufacturer as they will have information specifically for their product. They may be able to provide you with a website with product data or ask the manufacturer what process they used and if they have a MSDS (Material Safety Data Sheet) which may provide specific hazards if any, associated with your pots. Or try http://siri.org/msds to search for more information. Hope this helps.

  46. […] Food Safe: Some materials like plastics and metal can leach chemicals into the soil, so you may also want to select your containers very carefully if you plan to grow food. […]

  47. Janelon 31 May 2014 at 11:36 am

    What are your thoughts on root pots, particularly those made by Aurora Innovations out of Eugene Oregon? Do you consider these pots safe and good for organic container gardening? I have some organic tomato plants and herbs I want to grow in safe containers.

  48. Anne Gibsonon 31 May 2014 at 12:44 pm

    Hi Janel
    I’m not familiar with the Aurora brand of root pots, although the company seems to have an organic focus. Root pots do offer some advantages if your climate suits those conditions and also your budget allows for a temporary pot that will eventually break down. In response to their statement, “Made from 100% Recycled Material”, I would suggest you ask the company to provide more detailed information on their product. e.g. Exactly what materials do they recycle in the process? Where do those materials come from? Are they local or imported? Do those materials leach any toxic chemicals? Do they use chemicals in the manufacturing process? They would be the best ones to help you find out more. Recycling is a great concept, and I’m all for environmentally friendly and responsible products. When making a purchasing decision, I’d encourage you to think about the wider pros and cons of containers. If for example, you recycle toxic plastics that will leach into the soil, then it’s not the sort of product an organic gardener would want to use. I’d suggest you do your due diligence and find out directly from the manufacturer so you can satisfy yourself in this regard – they may also supply you with a MSDS (Material Safety Data Sheet). Please share your findings back on this page for the benefit of our readers. It would be good to know!

  49. Janelon 07 Jun 2014 at 6:09 pm

    Thank you for your thoughtful response, Anne. I did ask the company, Aurora Innovations, what materials they use to make their root pots. They stated their pots are made from recycled plastic bottles and fabric. This sounds concerning to me because of the plastic – I’m concerned about chemicals from the plastic in the recycled bottles leeching into my soil, especially when it gets hot outside. With so much information re: the negative impact of plastics on our health, it seems strange to me that a company with an organic focus would use plastic in a vessel that would be used for organic growing. What are your thoughts on these root pots now, knowing the materials from which they’re made?

  50. Anne Gibsonon 07 Jun 2014 at 8:43 pm

    Hi Janel thanks for sharing your research on the Aurora root pots. Personally, I think you have to decide for yourself if the product lives up to your expectations now you know it is made from recycled plastic bottles and may potentially have problems with chemicals leaching. I err on the side of caution where my own food gardens and the environment are concerned. There are many companies trying to do the right thing with their products, and others that need to realise that just because something is recycled, doesn’t mean it meets organic standards when it comes to growing food. When you dig a little deeper and do your research, sometimes you have to make tough choices. There are plenty of safe alternatives out there – why not start by recycling your own cardboard toilet rolls into seedling pots? They are free and can be buried directly in the soil where they will biodegrade and add organic carbon. I hope this helps!

  51. Kathleenon 14 Jun 2014 at 3:44 pm

    I want to attempt aquaponics but have found that large pots are super expensive. Though things like old washbins are the right size however im not sure if a metal bin is ok to grow vegetables in. What do you think?

  52. Anne Gibsonon 14 Jun 2014 at 3:59 pm

    Hi Kathleen, it’s hard for me to comment as there’s only limited information about the ‘metal bin’. However, the basic principles apply: Do your due diligence if you are repurposing. Find out the history re contaminants. Metals do leach especially when in contact with water so are generally better suited to short term projects with ornamentals like succulents rather than food. Metal + water = rust! So perhaps consider a material more suitable for growing food in contact with constant moisture? You could try Freecycle.org in your location & post a free ad for what you are looking for – perhaps you’ll find the perfect container!

  53. […] sturdy food safe plastic containers can also be used such as:  large yoghurt tubs, plastic soft drink or juice bottles, butter tubs […]

  54. Jamieon 16 Jun 2014 at 2:11 am

    Hi Anne
    I just built a vertical garden and planned to grow herbs and small vegetables in it. I stained the exterior and the part of the interior that would show above the soil with an oil-based stain. After reading the label on the stain, I am now worried that I made a mistake in staining the wood. Is it safe to plant herbs and veggies in these planters now?
    Jamie

  55. Jamieon 16 Jun 2014 at 2:50 am

    Could I line the interior with the plastic that the MiracleGrow soil came in? Thanks for the WONDERFUL site and great info!
    Jamie

  56. Anne Gibsonon 16 Jun 2014 at 12:10 pm

    Hi Jamie
    I think you may have answered your own question here! Sounds like the stain has chemicals in it, as most do. For food gardens, soluble chemicals that leach into the soil can be taken up into the plants via the roots. So if you don’t want to be eating contaminated food, you’ll need to think creatively about how you can still use your structure.
    Some suggestions are:
    1. Perhaps you can sit smaller containers or rectangular pots inside the vertical sections to grow your herbs and vegies. i.e. use your vertical garden structure as a cachepot.
    2. Line it – a barrier may help reduce any leaching. Perhaps avoid lining it with plastic – this just takes you back to square one! A dense weed mat perhaps that still allows moisture to drain through or a landscape fabric. You may have to research what’s available in your area.
    3. Use the structure for ornamentals instead!
    Hope this helps. Let us know what you decide to do and find out as I’m sure others would benefit from your research and decision.

  57. Anne Gibsonon 16 Jun 2014 at 1:03 pm

    Hi again Jamie
    My personal opinion is I wouldn’t! See my other suggestions. You may find it of interest to read more about MiracleGrow and the company that make it, Scotts here. It may change your thinking! Personally, I believe in doing my due diligence before buying any product now and choose to support companies that have proven they are not damaging the planet and environment. For me, this is an ethical decision and I work with brands I trust and that have organic certification where possible. Sadly, this is often one of the only protections we have, as consumers, as to what is in a product. Best of luck.

  58. Sheelaon 22 Jun 2014 at 6:22 am

    Hi There,

    I am going to try some organic gardening in pots. Came across some great resin planters at Costco called Kiri Resin planters which are labeled LDPE 4. Are these absolutely safe for growing fruit and vegetables?

    Thank you!
    Sheela

  59. Anne Gibsonon 23 Jun 2014 at 1:20 pm

    Hi Sheela
    Great to hear you are going to start organic gardening in pots. As far as I know LDPE 4 (low density polyethyene) is one of the safer plastics. However no plastic is 100% safe. Based on recent research I’ve read, under different conditions they can all leach some chemicals. There’s an article that explains more about food-safe containers @ http://modernsurvivalblog.com/preps/safe-plastics-for-food-and-drink/ which may be of interest. You may want to contact the manufacturer directly and ask for an MSDS (Material Data Safety Sheet) for more information.

  60. Heatheron 04 Jul 2014 at 8:40 am

    Hello,
    I am about to plant veggies into a large aluminum container. We bought a new horse trough and were hoping to use it for a raised bed. Have you heard of aluminum leaching heavy metals into soil?
    Thanks!
    Heather

  61. Anne Gibsonon 05 Jul 2014 at 1:04 pm

    Hi Heather
    Yes I have heard of aluminium leaching into the soil (particularly dangerous in acid sulphate soils according to the research I’ve read). You may find it useful to review the comments in this post relating to heavy metals to help make your decision particularly:
    http://themicrogardener.com/choose-safe-containers-for-growing-food/#comment-104687
    http://themicrogardener.com/choose-safe-containers-for-growing-food/#comment-156414
    It’s tough balancing repurposing with safe food growing practices. It comes down to doing your due diligence and this often means reading research papers (some of which are in the above comments). I hope this helps give you some food for thought and info you can use to make your decision.
    Cheers Anne

  62. Cherylon 09 Jul 2014 at 3:34 am

    Just found your site while searching for an answer to a question. Great site! I looked through all your comments and didn’t see this one, so I hope I’m not asking a repeat question. We have a smaller hot tub that has cracked over the winter and is now unusable without investing a lot of money. We have been wanting to put in some raised beds and are now wondering if it would be safe to grow veggies in the hot tub or if we need to be concerned with chemical leaching. Thank you so much for any advice you may have!

  63. Anne Gibsonon 09 Jul 2014 at 11:25 am

    Hi Cheryl, I’m not sure about the answer to that one. If it is a bath rather than a spa, then you could possibly use it as a wicking bed. If not, then perhaps check with the manufacturer for more information on the materials.
    Here are some wicking bed tutorials – however I don’t recommend using PVC pipes as these leach chemicals!
    http://mrc.wa.gov.au/Documents/Earth-Carers/EC-Newsletter-March-2013.aspx
    http://www.urbanagriculture.org.au/wp-content/uploads/2013/09/UAA-Fact-Sheet-2.08-Building-a-wicking-bed.pdf
    http://www.bellbirdsnpeashoots.com.au/2013/08/grow-your-carrots-in-bath-how-to-make.html
    Hope this helps! :)

  64. DIY Repurposed Garden Projects |on 23 Jul 2014 at 9:49 am

    […] food safe materials like untreated timber (preserved with linseed oil), rather than PVC, vinyl or metal gutters which can leach toxic chemicals into your […]

  65. Karenon 29 Jul 2014 at 4:26 am

    Hi Anne,
    Sorry if this is a repeat question. We have a old plastic heating oil tank that we have drained and cut in half. It is the perfect size for growing all the veg we need and we have given it a good clean. Would it be safe to use do you think? If in doubt could we line it with something? We’d really appreciate your thoughts.
    Many thanks
    Karen

  66. Anne Gibsonon 30 Jul 2014 at 12:50 pm

    Hi Karen it’s difficult to say. Perhaps you could ask the manufacturer what kind of plastic it is made from? I am not familiar with plastic heating oil tanks. Leaching from plastics is always a concern especially with food gardens. See what you can find out from them. Then you can make a more informed decision.

  67. Edon 12 Sep 2014 at 7:03 am

    Hi Anne,
    Could you provide any guidance on safety of materials used for hydroponic gardens? I’m interested in trying to build one, but am having a difficult time with general Internet searches in finding whether PVC, CPVC or HDPE-rated tubing is food safe.
    In blogs I’ve come across, some recommend that I find products that are USDA certified (fork and wine bottle stamp), FDA-compliant, and NSF-compliant. But those just aren’t things that you can find.
    I’d be eager for any information you had on safety of CPVC and similar materials.
    Thanks!

  68. Anne Gibsonon 12 Sep 2014 at 7:54 pm

    Hi Ed

    To be truthful, I’m personally not a fan of hydroponic gardens. I believe in growing nutrient-dense organic food in soil, as nature intended, so plants can take up the full component of minerals and trace elements naturally. Hydroponic systems also rely heavily on plastic and non-sustainable components, but that’s a personal choice. I am happy to share what I know. I have done a lot of research into avoiding chemicals and toxins in the garden, particularly where plastics are concerned.

    There’s a huge number of research papers, scientific studies and credible technical reports on the dangers of PVC. I am happy to email some to you or read some of the comments on this page for a few of the links from similar questions in the past. Basically, all plastics are liable to leaching – some more than others, depending on their manufacturing and exposure to UV etc.

    CPVC (Chlorinated PVC) is also a worry according to what I’ve read. There has been considerable research about the concern that these materials leach chemicals into drinking water and results seem to consistently agree they do. This is just a sample of the research that indicates leaching of chemical toxins occurs:

    Organotin Leachates in Drinking Water from Chlorinated Poly(vinyl chloride) (CPVC) Pipe
    Investigation of CPVC in Drinking Water – Read the Conclusions section which is a summary of the findings

    Organic and Organotin Compounds Leached from PVC & CPVC Pipe

    A Wiki article on PVC quotes under Health and Safety:

    “Degradation during service life, or after careless disposal, is a chemical change that drastically reduces the average molecular weight of the polymer. Since the mechanical integrity of all plastics invariably depends on their high average molecular weight, any significant extent of degradation inevitably weakens the material. Weathering degradation of plastics results in their surface embrittlement and microcracking, yielding microparticles that continue on in the environment, known as microplastics. Microplastics concentrate Persistent Organic Pollutants (POPs). The relevant distribution coefficients for common POPs are several orders of magnitude in favor of the plastic medium. Consequently, the microparticles laden with high levels of POPs can be ingested by organisms in the biosphere. Given the increased levels of plastic pollution of the environment, this is an important concept in understanding the food web.[29] However there is evidence that three of the polymers (HDPE, LDPE and PP) consistently soaked up POPs at concentrations an order of magnitude higher than did the remaining two (PVC and PET). After 12 months of exposure for example, there was a 34-fold difference in average total POPs amassed on LDPE compared to PET at one location. At another site, average total POPs adhered to HDPE was nearly 30 times that of PVC. The researchers think that differences in the size and shape of the polymer molecules can explain why some accumulate more pollutants than others.[30]”

    HDPE is apparently supposed to be one of the ‘safer’ plastics but you will have to make your own decision about what you choose to grow food in. However, research also is quite clear that Most Plastic Products Release Estrogenic Chemicals: A Potential Health Problem That Can Be Solved. In that research study, the authors concluded “Almost all commercially available plastic products we sampled—independent of the type of resin, product, or retail source—leached chemicals having reliably detectable EA, including those advertised as BPA free. In some cases, BPA-free products released chemicals having more EA than did BPA-containing products.” This includes HDPE products.

    You can learn more in How To Recognize the Plastics That Are Hazardous To Your Health.

    Personally, I keep PVC well away from my garden and try to use natural materials wherever possible to avoid contaminating my soil and food. I hope this helps provide some food for thought! If you need help growing food in small spaces, minimizing the need for water, please feel free to check out the many articles on this blog. All the best with your research!

    Cheers Anne

  69. Nancy Wilsonon 17 Oct 2014 at 1:34 am

    Is H Resin (Lowes Product) a safe product for raised garden containers. If not what should I get and a source please. Thanks.

  70. Anne Gibsonon 17 Oct 2014 at 11:47 am

    Hi Nancy
    I suggest you check with the manufacturer and ask for an MSDS (Material Safety Data Sheet) which provides technical and health related information e.g. whether the plastic is likely to be affected by UV or affects the environment in some way. You can also look on the product itself to find out exactly what kind of plastic the garden bed is made from. Many have a stamp you can use to ID. Plastics vary so widely – there’s just not enough information to comment further.
    Names of plastics can also be confusing. High density resin is sometimes also known as high density polypropylene resin. HDPE (high density polyethylene) is usually stamped with a “#2″ and polypropylene PP is usually a #5 to help with identification. These are two of the (apparently) safer plastics to use for food gardens. Recent research however, suggests that even safer plastics still leach some chemicals, particularly when under stress such as from UV sunlight. This applies to PP. This article on Polypropylene has some references you may want to investigate further.
    I also suggest you read my post on the Pros and Cons of Choosing Containers which has some useful advantages/disadvantages for different kinds of planters. Once you know what your short list is, you may even find a more suitable alternative. There are also many DIY planters you can make by reusing everyday materials. You can find the articles here.
    At the end of the day, I guess we have to make our own decisions about what to use based on the current research, space and budget we have. There are pros and cons for all containers but if you have another alternative, perhaps you could consider this instead. Hope this helps!

  71. Taniaon 26 Nov 2014 at 6:55 am

    What’s your thoughts on planting in old grape dip tins?

  72. Anne Gibsonon 26 Nov 2014 at 5:30 pm

    Hi Tania
    The old metal vintage dip tins have great character and were used as part of the dipping process in the grape industry in decades gone by. The grapes went through a chemical process so there would have been some residue. Although that was a long time ago, you may want to consider preserving such a unique (and often expensive) container. I’d suggest using it as a cachepot (outer decorative container) and plant into a smaller rectangular plastic pot inside it. Metal degrades over time (especially when in contact with moisture), so this option would allow you to plant into a safe pot while still enjoying the beauty of the dip tin. Hope this helps. :)

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