Garden bed corydline conundrum - help appreciated

dilby

Hi all - Hoping some kind folks could help me with some feedback; I'll try to keep it as short as poisslbe. I had an existing bed around an old deck that I had to rip out due to all the timber rotting, and I have replaced it with composite decking and am about to put new sleepers in to reinstate the beds. At one point it looked nice, and was full of plants that reminded me of my home in Australia and of holidays in warmer climes, so a real mediterranean feel with gritty fast draining soil. But it was time to restart with most the plants, and im beginning again with taller trees that can act as screening by sitting above this 5ft fence. This photo is only 1/4 of the length of the bed and I figure i want to choose 4 tall plants, of which I hope to keep these 2. The palm although too far into the corner for my liking has to stay as it's grown into too many rocks that were in the bed (I added way too many for draining when i didn't know what i was doing - still don't!). Next is the cordyline which grew way bigger than I thought it ever would and I believe I need to move as it's too close to the palm. So two main questions:

1) What are my chances of moving that cardyline successfully, and does anyone have any top tips? As you can see I've dug down quite a bit but am at the point now where I'll definitely need to hack back some roots. 

2) Also can a cordyline be buried deeper so it's not as tall, in the same way as say a tomato plant can (perhaps there's a name for this kind of plant). Sounds counterintuitive but it's so fast growing that i don't want it to grow too far above the fence.

3) Does anyone have any suggestions for remaining 2 trees? I have a eucalyptus azura that I would love to put there but I've read mix things on how easy they are to prune and keep restrained. (the bed is about 80cm front to back and will have good depth. I've also toyed with a birch tree - given they don't fit the theme but I do love them and as we are near a busy road i thought the sound would be nice, but I'm not sure how they'd fare in that setup.

Image attached (please excuse the mess - in the middle of sorting it all!)

Thanks so much to anyone who has managed to make it this far!

Hostafan1

I believe cordylines have a tap root, which, if broken ( and they snap easily ) will result in the death of the plant. 

thevictorian

Hi, cordylines are incredible hard to move as mentioned above. There was a thread not long back about moving them and I needed to try the same thing not long after and saw why people suggested it was near impossible. I'd guess yours is a bit taller than the one I had to dig out but the tap root on that was thicker than the trunk and went down very very deep. It would have been impossible to get it out.
The good thing though is they respond well to a good hacking back so perhaps next spring you could just chop the trunk at a desired height and it will resprout a new top (or sometimes they sprout from the bottom but general when the cold gets them). It's not in to bad a position from the picture, space wise and since moving it would probably kill it (they can be grown from their trunks though so if you do cut it down, try planting the top with lots of the foliage removed) I'd be tempted to leave it.
The palm will keep growing and I'd probably add more instead of going for a birch because raised beds are not the greatest conditions for temperate trees because they drain so quickly. You might be ok with an acacia dealbata as they take well to prunning and don't mind good drainage. Another option is an olive, which should do well in the spot if you don't get cold winds blasting it.