For raised bed, you will need also top soil, or native soil.
I used more than 50% topsoil, about 30%+ compost, and the rest all kinks of composted manure (Cow, chicken), peat moss, .. and the sand was included in the topsoil(Actually was called GARDEN MIX)

Thanks for that but I was wondering whether top soil was really essential as Mel the sq foot gardening guy says equal parts compost, peat moss and vermiculite, no mention of soil. So I thought maybe it wasn't necessary...

In my personal opinion, topsoil (aka dirt) is beneficial.
Where does the SOIL come from ? The answer is it is decayed rocks and stones over thousands of years, then little by little mixed with composted plant parts. So in effect , topsoil is a combination of inorganic and organic matter. They both have ingredients that plants can benefit from.

Square Foot gardening(IMO) is something like pot/container gardening and it is not an economically sound growing system... simply, the costs out weights the benefits.
Imaging making a 1000 square foot garden with that method !!
It will cost a fortune.

Thanks Seysonn, I got you, yes you are right about the cost. Cheers for the help.

If you haven't already, you should check out the Square Foot Gardening forum. There are a lot of discussions about what mix to use, just search "Mel's Mix" over there. The forum's FAQ has interesting information as well.

Personally, I'd use a mix of compost and soil to fill the beds.

Rodney

Here is a link that might be useful: Square Foot Gardening Forum

Is there a particular reason you feel that SFG is necessary? Do the locals have trouble gardening in the native soil? Maybe you are making life harder than it needs to be. Whereabouts in Sri Lanka are you located?

Relating to what Flora said :

In my previous location, in GA, I created a garden area of about 600 sf, where it had been all covered with wild berries, thorns, small pine trees, all kinds of perennial weeds.
The native soil was red clay that would harden like a rock. It took me gradually two seasons. It was a good physical activity for me, better than joining a gym. . In the process, I did not buy even a single bag of soil, manure or anything. I hauled topsoil , leaf mold, pine straw, from the wooded areas. I found a farm and got free horse manure. I buried fall leaves, brought a lot of earthworms from other places, throw them in the garden, added lime....
I created a beautiful blend with that red clay soil and all the organic matter. I grew just about any garden plants I wanted there successfully. Again, without buying a bag of any supplement.
I have heard a lot of negative thing about clay soil. But once you amend it, it is the best thing.

But the I understand that not everybody has time and instead they have finances to do it quickly with less efforts. That is fine too.