Have you hade success doing this before? I am trying to do the same thing with a Norfolk pine. They always come as a group and I usually separate them, but these had roots that had grown together, so I tied the trunks together hoping they would grow together, or at least betrained to grow very close to each other. I have only had them this way for a couple weeks, with a note to myself not to touch until at least March.
I took 4 suckers that grew through the pavement and tied them together with sowing thread (stupid, I know) but by now the tree has grown over its thread bounds and they’ve become invisible. And I have a nicely proportioned little tree to show for it
