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.