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.