These are only borderline hardy, so you'll need a sheltered spot - if you're near the sea, there's much more chance they'll be okay over winter, but it's probably safest to plant in spring (assuming you move them in their pot to a greenhouse or conservatory most years).

Info from the RHS here, including winter protection

https://www.rhs.org.uk/advice/profile?pid=104

Thanks for the info Bamboo.
I live not too far from the sea, I left it outside last year & thankfully it survived ?

Good drainage is the key for anything borderline hardy.

and bury it deep. let the plant die back and in the spring remove the bulb from the compost and plant 6" deep. Mine have come through for 4 yrs on the trot now.

Thanks for Info Andrew & Seaburngirl.
Bye the way I've renamed it "My Triffed" LOL