Hi Beth…
Chances are if you ever spent time in science class you will have heard the phrase “angle of incidence = angle of reflection”. This might sound technical but it is easy to understand, particularly if you think of a tennis ball being bounced off a concrete floor; you pretty much know that if you bounce the ball at the angle onto the floor it will bounce back up at a similar angle in the opposite direction.
Light behaves exactly the same way around shiny surfaces… if you are looking at reflective surface, like this water, you can be certain that any reflective detail you notice, including bright or dark patches, will have come from exactly the same angle that you are looking from, but from the opposite direction.
With this fact in mind, most experienced photographers learn that if they are photographing a reflective surface, like calm water or a panel on a new car, they have to look beyond the subject and look at the source of the reflection to appreciate how that photograph will look.
I know that you are concerned about the band of bright light in the left of the image; what you really needed to do here is to move to your left, aim the camera slightly to the right and you might have had more darkness in the background to work with. As another option, you could have moved back from the subject and then zoomed in with a longer lens, like a 300mm. This would narrow the “field-of-view” so that you could work more easily with that dark shadow in the background.
There is another trick that some photographers will often use and that is to get a friend to hold a light disc (one of those circular reflector panels) behind the subject to even out the light, so that in effect you are looking at a reflection of the light disc rather than the sky. These light discs are available in a range of surfaces including a black and silver combination (most of the time you would use the silver side for adding light, but in this instance the black side for subtracting light). If it is any consolation… in the past I have actually put black cloth between two light stands while standing in the middle of a stream just to manage light … the only challenge is carrying everything into the location.
As for how to improve this image… my advice would be to go back and have another go whenever this small plant is in season again, but this time get closer to the subject, and maybe get a friend to help you manage the background.
Cheers, Anthony