A "No Nails" Raised Bed

We are slowly trying to become self sufficient at our property and have a piece of land that has poor access for the mower etc and is covered in rough grass, so I have decided to put in a raised bed and grow root vegetables (potatoes, kumara etc). See before and after pics

The raised beds seem to be much more successful for growing and I have already built several (photos are included in this I'ble) but this is the first one that I have properly documented.

The basic construction is the same for all the ones I have done, just small details/shapes/sizes etc have changed

The whole thing is made from 6x2 H4 timber (or 150x50 if you are metric) and I used 6m lengths to minimize the cutting

These can be made with no nails allowing them to be deconstructed if required, I am going to use a few nails as these are going to be in for good and make the whole thing more stable.

EDIT For all those commenting that H4/ pressure treated lumber is toxic, please read the text

1. The whole thing is lined with plastic to prevent any chance of chemical transfer

2. Arsenic is no longer used in pressure treatment (and hasn't been for many years)

3. Studies have shown that toxic transfer is a MYTH!!

4. I didn't build out of cedar as it is eye wateringly expensive in NZ

EDIT2 if you really want to know the dangers (or lack thereof of using Pressure Treated Timber in raised bed go HERE www.naturalhandyman.com/iip/infxtra/infptforraisedgardens.html

I ordered a dozen 6m lengths of 6x2 rough sawn H4 timber (H4 means that it is treated for in ground use, mine are above ground but it means they wont rot any time soon)

I got this on sale at NZD $3;60 per metre + tax (so about $4 a metre) so $288

I decided that as there was space I would go for the easy dimension of 6m x 3m, so I cut a couple of the lengths in half with my compound mitre saw

So I laid the wood out in the area I am going to build, just to get an idea of the dimensions.

It is also a lot easier to build in situ rather than build elsewhere and dismantle/reassemble

As yuo can see the grass in this area is pretty rough ( I will dig this out later) also the area isn't flat so I will do some jiggery pokery when building.

I took the opportunity at this point to move all the wood over (as I was feeling strong)

So for a "No Nails" construction there has to be some way of joining the wood., you could try the powers of positve thinking, but it is much more reliable to notch the timbers.

I marked out the position 100mm from the end amd then set my circular saw to a depth 1/4 of the timber width (ie 1.5 inches or 38mm) In reality set it a fraction more than 1/4 to ensure sufficient depth ( I went for 40mm)

I then made several parallel cuts and removed the waste wit a chisel, on completion the bottom of the notch was cleaned out by sideways movement of the circular saw (you can use a chisel but power tools are quicker!)

So carry on and notch the other side the same way and both sides of the other end, repeat on all the other pieces

As you can see I checked the notch width with a piece of scrap 6x2

You may find it easier after the first couple of pieces to partially assemble the next laye and transfer measurements upwards for accuracy of assembly

Now you can either cut all the pieces and then assemble or as I do cut them as you are going as sometimes there needs to be a bit of adjustment and it's better to do it as you go along.

As you can see the area is a bit slopey so I will level it on bricks and take care of that when I fill it

the top "short ends need a piece of 6x2 cut in half lengthways but the same principle applies

To all purpose at this point it is complete, ready for filling etc but a few finishing touches make it more practical

It is always nice to have somewhere to sit at the edge of a bed when weeding, planting etc, so a piece of 6x2 on its side makes a convenient perch.

This was the only place I used nails in the whole build, to secure this on the top.

The corners all have half lap joints to make it all a bit neater, again just cut out by making 1" deep cuts with the circular saw and cleaning out with a chisel

I will line the inside walls with plastic (old feed bags) to minimise the chance of rot, however being H4 it shouldn't rot in any case.

Then will have to fill it, I estimate it will take 9 cubic meters of soil -- another day I think, at least I have a big pile of top soil close by!

The whole construction took a little under 4 hours to build, could have been a lot quicker with a helper to lift some of the bits (and if I didnt keep putting tools down and forgetting where)

Check out my other I'bles for different takes on raised beds--- I have built a few now!! There is also one pictured above which is a slightly more complex design - but same principles apply (this one is 6m x 6m)

Once filled I use weedmat and macademia nut shells as a mulch as we are on tanl water and thus want to keep watering to a minimum

This mulch along with the plastic lining mean that even at the height of summer we only have to water once a week

Also when filling I do alternate layers of the sandy soil we have, then topsoil (3 inch deep layers) topped off with about 4-6 inches of good quality compost or manure ( I get Alpaca poo by the truckload from a neighbouring Alpaca farmer--(don't know where he gets it from though!! :-) )