A few months ago I removed a lot of over grown shrubs; the soil is clay based topsoil on top of solid clay. The top soil is about one spade deep. I don’t think the garden has had any compost for many years.
I am going to double dig before planning the roses, so how much compost should I put into the subsoil and how much into the top soil. I have a source of compost from wholesale market fruit & vegetable waste and cost is not a limiting factor. (Organic content = 100%, C:N ratio c. 15:1, pH c. 7.5)
I am also planning on adding more worms, as there seem to be very few in the ground. All of the beds will be covered with compost or wood chipping every year, but this is my only chance to properly dig-in compost.
(We are in the North West of the UK)