sausmatoe wrote: ↑July 22nd, 2021, 11:13 am
and the soil is super hard on top...
For Sydney, I wouldn't do anything until about October/November. I wouldn't even cut back any of the branches.
From what you have said, it means it has been growing in that pot for quite a while without a repot, thus the roots will be way overgrown and presumably very pot-bound.
Now is not the time to work something that is probably going to require a very heavy root removal and difficult seperation to get anywhere.
The usual purpose of the repot is to open the roots up and remove the old mix and cut back the roots and replace with a fresh mix.
But this means its going to be quite a shock from your description.
Of course you can repot now, but why would you. Wait until the tree is in its fast growing phase for Oct/Nov to do a very substantial root overhaul.
However, if you are keen as mustard and bored as a schoolboy in lockdown, then go for your life... you might get heavy sulking because of the compact roots and amount of cutting you'll have to do, and we're still in very cold days/nights.
I'm about an hour north of you, and from memory I have only lost a few Casuarina from winter repotting (from about 300), but that was because they'd already had terrible root-rot and serious drainage issues to begin with.
Thats just my 2cents from experience from Casuarinas.
When I was 20, I would have hacked it back immediately, smashed the roots and stuck that sucker into a new pot without a second thought.
But.... thats youth.