They are trees, so essentially as large as you allow them to get.

RP1

I will reach 30 feet in your locale.

Not planting close to the house is a good idea! I would choose a location that gives a glorious
view of the plant and keep it trimmed to develop a good structure and certainly keep it pruned
to control it's growth rate. Cananga is very tolerant of pruning.

Ankrara's Hobby Corner

Thanks for your ideas. Maybe I should take the middle out of them as they are? I don't think I have the heart to do it though!! They look like they are going to flower. L