Lionel wrote:
Hi guys,

My wife and I have just bought a house in Brisbane and we plan to fill
the yard with fruit trees and gardens.

The soil in the area tends to be a clay type soil on top of shale. It
takes a lot to get wet, but once wet stays that way for weeks.

I'm wondering two things:

1. For trees such as citrus, what is the best thing to do to give them
the best chance of a fruitful life? I noticed some people heap the
dirt.

This is essential where there is poor drainage. Plant them into a mound not
a hole and if at all possible put them on a slope or if it must be flat the
highest flat area you have available as long as it is in full sun. If
planted into a hole it will fill with water, the roots will rot and the
citrus tree will die.

Make the mound from soil scraped from around the area, imported loamy soil,
organic material, compost, manure etc plus gypsum. Add lime if required and
stir. The water will drain out of the mound and run across the clay giving
the tree a chance to establish its roots without water-logging.

David