When does a plant start to smell?

at what stage does a plant start to smell? is it during the flowering stage?

after seedling growth it gets more of a smell
but evan a seedling smells

my plant smells of nothing or maybe i cant smell my plant for the paint smell in my room hmmmmm

mine smelt from day dot but now its 20 days into flower its really started to stink.

Mine is about 2 feet tall and I still cant smell anything O_O