METHOD

A square hole is preferable as it encourages the roots to travel out into the corners
instead of curling round the circumference of a round hole.

Add to backfill and mix thoroughly :
1 kg of Gypsum and
20 L (approx. 2 shovels) of compost - organic soil conditioner
impregnated with trace elements

In bottom of hole dig in thoroughly :
1 kg Gypsum
¼ bag of Compost
200g Osmocote Plus
10 L (approx. 1 shovel) of compost scattered on surface after planting.