I don't think it's going to root with just a leaf and leafstem - it needs to be a cutting taken from a main stem.
See information here about preparing a semi ripe cutting http://www.gardenersworld.com/how-to/projects/creative-projects/how-to-take-semi-ripe-cuttings/301.html
thanks Nutcutlet however I think it's just a stalk however it is long so I'm not sure?
If it's more than just a leaf stalk there will be a join where it comes off the stem.
So Daisy has suddenly become Ryan the gardener15 - that's the quickest gender swap in medical history !!!
Daisy, Daisy, give me your answer do,
I'm so crazy oh (maybe I am)
I wonder if this Ryan is the same Ryan that we knew from before ...
I wondered at first but the profile doesn't read like young Ryan.
I'm sure if it is he'll tell us