Leveling Garden - Structure & Top Soil

curtis.kinsley-smith

Good morning,

Our rear garden has a slope from rear to front and right to left, and I would like to level it out so it's nice and flat.

I have a builder booked to build a small retaining wall around the outside to hold back the neighbours garden.

But my question is more aimed at the part after the digging and wall is in place

It looks like my garden is currently structured like this:
10-15cm of soil with grass
A Layer of sand (varies greatly in depth)
A layer of rubble (3-5cm diameter stones)

My question is if I dig out the above to a level gradient will I need to re-add a layer of rubble and sand before the Top Soil again....?
Or should I be able to simply place a 15cm-20cm layer of topsoil down for the turf to be laid?

Thanks,

Curtis

Chris-P-Bacon

Is the sand & rubble(?) natural or "made ground" (placed there as a result of past building works?... it will have brick or concrete in it for example)

Without photos and knowing how steep your gradients are or how big an area it is its a bit tricky but generally speaking I would strip off the topsoil and stockpile it out of the way. You can then place the subsoil where its needed - depends on where you are "cutting or filling" to make it level.
Topsoil isn't stable in so much as it wont compact or take weight / structures / paths / patios etc. Topsoil will also sink, degrade and possibly erode (and get very sloppy when wet).
As a rule of thumb 6 to 12" of topsoil is enough for horticultural use. It will improve over the years with organic mulches etc.