Hard Soil and Clay

An area in my garden has clay soil and only receives afternoon sun from around 3pm. In summer, the sun can be so strong and in winter it may receive no direct sunshine. I’ve tried planting roses, peonies and hydrangeas but to no avail. A friend suggested I try planting cranberries. Do you think they will grow in this area? Any suggestions?

We are in Rolleston and are making new gardens. The soil is free draining but clay below. What would be the best to put on it for the growing of vegetables and flowers, especially gerberas? 

I would like to create a lovely vegetable garden but my garden is predominantly comprised of hard yellow clay! Can vegetables grow well in this hard clay? How much clay can I dig up without disturbing the garden’s soil structure? And can I mix the clay with compost to make it more beneficial for my vegetables?

My flower and vegetable gardens are affected by liquefaction brought on through the Christchurch earthquakes. How will this affect growing flowers and vegetables? What can you grow in this soil?

We are in the process of enhancing an area of a local volunteer organisation, by establishing a native garden. The area is in a gully where the soil is hard with a lot of clay and poor drainage. What should we do to ensure the soil is suitable for growing plants, shrubs etc. We plan to plant Autumn. Is this correct?