Digging beds from scratch - how deep and what soil?
We are renovating our garden. The previous owner covered half the garden in 6" deep concrete and the other half in paving slabs (the builders are outside digging it all up as I type, ready to be loaded into a skip on Monday).
Because of all this, we are essentially starting a garden on a bare site. We will be laying some turf and digging beds. We won't be growing veggies in the beds, just shrubs, a few climbers, etc. The 'soil' beneath the concrete and paving is very clay-rich. My question is how deep should we make the beds and what soil/compost should we buy to fill the beds? I'm staggered by the cost of topsoil but we do want the garden to actually grow, so we are prepared to invest the money.
As far as the lawn is concerned, my understanding is that the topsoil needs to be at least 6" deep, correct me if I'm wrong!