I'm not a huge fan of black and white photos of flowers b/c I think their colors against their backgrounds tell most of the story and make a photo interesting.
Judging the shot the way you PP'd it though: I think the actual flowers are OOF, along with blown out edges which makes the flowers look like one large blob instead of separate entities.
It's ok. To each their own. I am in my "black and white period". I find white flowers a hard color to photograph without blowing something out. Epically right in the midday sun.
Well, you didn't provide any of those details while posting your shot. How am I supposed to know the flowers are white and in midday sun? lol.
You might want to post a little background on your shot to leave us with some info to CC on and you might get some hints on how to shoot it better next time.
The colour photo is a lot nicer than the black&white version and you got the whites ALL RIGHT in colour, much "righter" than in the b&w version, where it looks too bright.
And rarely do I find that the greens come out good enough in b&w versions, when they are represented by a dark grey, blackish "colour".