Well, there's no arguing about taste.
While in general I do what Manfred suggested--use tonality controls to increase the tonal range of photos that have a narrow range (like this one)--that isn't always what one wants. For example, I often don't do that with night photography. However, in this case, I found the limited tonal range in the original to be somewhat drab. That's just my preferences.
I also found the large amount of empty space unbalance.
However, given the goal of keeping the background subtle, I can see reasons not to apply tonality adjustments to the whole image.
So, for what little it is worth, here is my very quick edit. I selected the flower in order to brighten it without brightening the background. I applied levels and curves adjustments to the flower, and I cropped the image. That's all I did.
Again, just my taste.
