Is my grevillia dead

My grevillia has gone very woody and brown, only a few green bits left is this dead, also the grass around it got water logged and died which was only put down 12 months ago, has this caused the grevillia to die, please help

 

Well grevillea does like well drained conditions slightly on the acidic side.

If you caught the hard freeze in December that wouldn't have helped either, they are not totally hardy in general, some are hardier than others.

 

I lost a few grevillea in the hard freeze before Christmas, though some varieties like Canberra Gem and victoriae are fine. If there are some green bits, it may recover. As Pete says, being Australian they need well drained, fairly poor acidic soil.

 

My Canberra Gem is barely alive, several -6/7 c's did for it. Even cutting it back I can't see it ever making a decent shrub again, will probably have to dig it out.

 

I had a Canberra Gem some years ago and I actually killed it by cutting it hard back that was without frost problems, I think they have difficulty shooting from really old wood.

Might be worth trying a few cuttings from the green parts @strongylodon

 

That's surprising @strongylodon - we had -10/12 around here before Christmas and mine looks completely unaffected! Yet an adjacent plant of G. Clearview David is totally dead. Of course it may not be Canberra Gem, but looks it from the flowers...
Anyway, as @pete says, worth using those few green bits for cuttings.

 

I've been looing round today and I'm finding that the Cordylines are dead at the bottom of the stems but alive further up, I also have a really old large shrub of Hebe that has green leaves and shoots but the gnarled old stem appears to be dead.
Its as if things are dying upwards.

 

That's odd @pete - maybe the wet after the frost started them rotting

 

Or maybe the temperatures were that bit lower nearer the ground.