Cutting back/rejuvinating a Bird of Paradise Strelizia?

Question

Hello, our new property has an enormous Strelizia (H = 2.5m, W = 2.5m) that’s not been tended properly over recent years. It’s flowering but struggling and ragged. I want to do more than simply trim – it’s too big for its location and it clearly needs rejuvenation, thinning, TLC etc. My inclination is to cut the whole down to something around 400-500mm high and remove about half the root stocks (so it’s about 800mm wide) including thinning out what remains of the root base. I’ll probably also propagate from some of the root stock removed and plant them elsewhere.
Would doing that be too savage? Will it survive and return to good health?
BTW: I’m writing from the northern part of New Zealand, not tropical but temperate – excellent growing. It’s presently late summer, with plenty of rain and temperatures still 20 degrees plus (Centigrade).
You advice would be appreciated.

Answer 1

Because these plants grow well, they often outgrow their location.
They have thick, carrot like roots that will sustain the plant if you cut them back.
The Bird Of Paradise will come back with fresh leaves, but it will take awhile.
When you are faced with the overgrown plot that you describe it may be best to dig up the plot and replant a smaller division into the area, or move them entirely.
Either method will result in a cleaner area but both will need time to recover and bloom again.

https://www.gardeningknowhow.com/ornamental/flowers/bop/bird-of-paradise-pruning.htm