Proposed New Growing Area & Issues with Wooden Planters

We have been in consultation with the Great Estates team over recent months to come up with a design for some new organic growing plots for residents to use. Last week we were presented with a proposal from Ruth & Sophie for a scheme containing 10 wooden raised be planters, as detailed here.

However we have major concerns about wooden raised be planters, as the existing planters that we have (only 10 years old) are now falling apart. Please take a look at the images below:

I sought the advise of Oli Hayden at Walworth Garden, who has recently built some raised beds, using reclaimed tropical hardwood sleepers, and did extensive research on the various options available. Here is what Oli told us:

I contacted the Forestry Standards Commission (FSC) and sought their advice.
All of our existing raised beds are now decaying and will need replacing. They are constructed from treated softwood and are now exuding tar. This wood treatment was common in those days (the 80’s). They need constant attention. Before I arrived they had been clad in wood so that the oozing tar did not show so much. This cladding is also now decaying.
New softwood sleepers are pressure treated. This process is considered toxic. They involve the use of copper, chromium and arsenic. Sleepers that are treated like this begin to rot from the inside and then collapse, releasing their toxins into the soil. Burning them is even worse.
There is apparently a new and ‘safe’ system using an e- Tanalith for wood preservation but little is known about it.
This all on top of the fact that the life span of these sleepers is about 15-20 years and then more trees will need to be cut down to replace them.
The FSC recommended to us that the most sustainable form of wood to use for this purpose is reclaimed tropical timber. The timber already exists in this country and has been used already so we would be recycling. The timber is from various hardwoods which do not need treating. Wood treatments are generally toxic (pressure treated or not).
Other possibilities we considered was green oak, but the idea of cutting down oak trees so we could grow plants did not sit well and anyway green oak contorts as it becomes seasoned. Reclaimed or recycled oak we would have considered but supplies are not easy to come by.
Anything reclaimed or recycled is always going to be better for the environment and for us, this should always be the first and last thought.
When I work with community groups, they almost always start with ‘we want raised beds’ and the question I ask is why? This current obsession with raised beds is unnecessarily ripping down forests. Unless there is a good reason, (wheelchair accessibility?) I would always plant into the ground where possible as maintenance levels are reduced because the plant can access ground water. Raised beds by their nature are prone to drying out and at a time when we should all be considering water consumption, I would be asking if the raised bed is our best course of action.
From all the research that I have done, wooden raised beds are a short term solution, and are really just a future eyesore to place on the estate. We also need to get more details on the type of timber that they plan to use – reclaimed tropical hardwood or treated timber? If treated timber, is it pressure treated softwood and therefore toxic? Will the company contracted to deliver this project offer a 10 year + guarantee to repair and replace the timber beds if they fail? Can we please visit a reference site where a similar installation has been in place for 10 years or more?
We had specifically asked the GE team to replicate the existing engineering brick raised beds, which were originally built in 1961, and are still in excellent condition.  Our original request for two brick built raised beds (that could be sub-divided into individual plots) would also allow us to easily install a soaker hose irrigation system, that would allow a hose to be connected to one hose connection, and simultaneously water all the plots.
On the basis of the research that I have done, I do not see this proposal (in its current form) as any addition to our estate, and for the second time in this project I am quite disappointed that the GE team have not listened to our concerns.