In article ,
says...

I have 4 Cordyline australis in my garden. We live in south west
scotland and they have withstood the 2 winters we have been here ok. I
believe they are around 10 years old. Over the last couple of months
each tree has sprouted an inner almost foliage/seed growth. All the
leaves which were a rich green before are now starting to yellow and
look distressed, Should I cut away the inner growth. It is totally
different from the leaves and looks very healthy, but I very much dont
want to lose the beautiful spikey leaves of the palms. Photo attached.




--
GardenReg

Could be they are trying to flower, the flower spikes come from the
centre and normally coincide with the oldest leaves yellowing and
dropping off.
It is also more than possible that the plants are suffering from frost
damage as the temperatures this last winter were quite close to killing
them back to the ground.
Either way although its ok to remove yellow leaves leave the rest alone
and await developments!
--
Charlie Pridham, Gardening in Cornwall
www.roselandhouse.co.uk
Holders of national collections of Clematis viticella cultivars and
Lapageria rosea