Tetrapanax have roots close to the surface and together with rotting the main trunk, you will slowly suffocate the plant. Dig it up or leave it a hallow around it.

Several months later...

I used Sambucus nigra Black Beauty against my white wall as it gives a pleasant contrast. I did think of copper beech but I don’t need a screen there and it is not as light.

What time of year do you do this?