Which garden plant is this?
Looks like oriental lily to me.
No, not a lily.
Kaffir Lily (Schizostylis)?
does looks like a.beladonna or even crinum to me.
Well done. Crinum...powellii i think. I posted a pic on here a few weeks ago when it sent out its first flower, which is a first for me with this bulb. It has since sent up two more flower spikes and they are up to 4 feet tall.