If you are going to grow leafy vegetables I would suggest Living Earth mix. Cost around $6.00 per bag from Central Landscapes and Garden Supplies if in Auckland

I put cardboard on the floor of the raised bed, as it was set on part of my grass, and filled with supergrow vege. 

https://gardenmakers.co.nz/product-category/gardening/soils-composts/

For a raised bed, I believe you can get away with soil at the base and good compost up on top, as most of the 
veges are shallow rooted.  

I wish I had put weedmating on the floor as there  are roots that are coming up from a cypress tree close by.
I let the plot rest during winter and only grow veges during spring and summer.  

If you have more than 1 raised bed, think about rotating your crops every year. Perfect if you have more than 4 raised beds
Good luck

qwertee:

I wish I had put weedmating on the floor as there  are roots that are coming up from a cypress tree close by.

At the bottom, any kind of yard waste will do - leaves, sticks, dirt. Save some money filling up the whole thing with purchased soil. On top of that, get some clean soil from a reputable source, and mix heavily with quality compost. Personally I’ve found commercial compost to be mediocre at best - but it’s a good start. If you can, start making your own compost from here on.

I have a couple large raised beds that I like to cover crop over winter (clovers, mustard, vetch, etc). Right about now I chop that all down and let it lie (‘green manure’), cover with a thick layer of compost for a couple weeks then start planting. No turning of the soil. Only takes a season or two for it to become a deep, rich, organic soil.