Building a Raised Garden


Steel Raised Garden Kitset (from TradeTested)

If building isn’t your thing you can buy raised garden kits – these range from tarpaulin type, to metal.  (some assembly is required)  There is a huge range in price, so hunt around, there are lots of options out there.

If you are looking for something more permanent, then build your own, from wood, concrete, brick…  Each has it’s merits and it’s drawbacks.  The choice is yours.



Potato Bag - Great for patios or decks (From The Warehouse)

Potato Bag – Great for patios or decks (From The Warehouse)

A couple of things to bear in mind:


  • Height – Do you want a no-bend garden?  Do you want to be able to easily dig?  How are you going to fill the garden (soil/compost)?  How much room do your plants roots require?
  • Size – Don’t make a garden so wide you can’t easily access the middle of.  1.5m – 2m is a good size assuming you can get to it from all sides.  Again, be aware you have to fill your garden once it’s built.


Wood – Treated or Untreaded?

For every website I find that says don’t use treated wood, I find one that says do…

I have one garden using treated wood – I’ve lined it with plastic at the sides to avoid any leeching.  I also have a couple made from pallet wood (untreated).   How long will they last?  I don’t know.

If you are using railway sleepers or similar – be wary of what it has been used for or what could have leached into the wood previously.

Building a Timber Raised Garden

As timber is by far the most common choice here are some step by step instructions on how we built our new raised beds.

STEP ONE:  Making some decisions

Choose your site – Sunny and protected from the wind in an easily accessible area.  Flat is best, if it’s not flat you’ll need to do some digging to make it level.

Choose your size – Don’t make the garden so wide that it is impossible to reach the middle.


STEP TWO: Building the frames

DSCF3767I cheated a bit here:  I found some pallets (Cypress and Douglas Fir) that had lengths of 1.52m, and lengths of 2.24m.  The wood is 65mm x 40mm) – So that is the size of my garden. I simply pulled the pallets apart, (well not simply if you have ever dismantled a pallet you know what I mean).  I bolted the pallet wood together using 90mm coach bolts (with washers).  I recommend bolts over nailing because over time the nails will pull and walking around your garden nailing everything back together will be a regular thing.

STEP THREE:  Attach your uprights

It is possible depending on the height you choose to just place the uprights on the ground.  Here I’ve dug mine in 40cm.  (Which was easy for the first 18cm and then I hit hard clay {argh}).

In our case I found it easier to put the frames on their side, clamp them together and attaDSCF3762ch the uprights.  Then lift/drag the whole thing and drop it into the pre-dug holes.

This is the point where the spirit-level came out and we checked the garden was on the level. (Ha!)


STEP FOUR:  Lining and Filling


Sides lined, cardboard layered on the bottom

We lined the sides with weed-mat and then lined the bottom with cardboard boxes.  The cardboard was well watered before soil was added;  This was to avoid wicking where the dry cardboard will pull moisture from the soil and away from your plants.

Other options are to line the bottom with weed-mat or layers of newspaper (again wet it before adding soil), or line the sides with black plastic.  Do not line the bottom with plastic for obvious reasons.

Once the base and sides are done, start filling.  Mine was a mix of vege mix, sheep pellets, and a wee bit of compost.  Fill it right to the top.  You will find it starts to settle pretty quickly, but you are going to build this up again over time by adding compost and mulching around your plants.


STEP FIVE: Watering and Mulching


Using a cheap irrigation starter kit and a few extra bits we created a drip feeding system for the garden.

Finally we laid mulch over the garden.




STEP SIX: Pest Proofing

Again there are a lot of choices for how to pest proof your garden from commercially purchased tunnels and domes to DIY methods.

Your options for creating the frame include: bamboo, fibreglass, plastic pipe, wood