If you had a retaining tire wall.

I have seen tyre walls to hold back the soil where a house is built into a bankside? 

Your new house to be is being built on the flat isn't it SC?

Personally I would just let a tyre wall look after itself and see whatever arrives in the wind? It would also depend on what aspect it was and whether it was shaded or not I would imagine?

You could also, chuck a wildflower mix of seeds at it and see what comes.

Our finished floor level is lower than the ground level at the back of the house. As we discovered yesterday while studying plans. Also it’ll be very visible from our living room.