sorry I didn't answer your question.

trops are notoriously difficult in the nursery because of the deep rhizome
6-9inch. and need to keep the root cool (difficult in a pot) This is why you
seldom see it for sale.

They like cool northern climate so do well in Yorkshire but do prefer acid
to neutral soil with lots of humus and sand added. ( Burton Agnes is on
chalk with some clay over)

the conditions under a C. leylandii hedge do tend to acidify

Roots in shade main growth in full sun.

If you get it established it will be fine. but not an easy one this but such
a good plant it is worth trying