I captured this image of a single dandelion the other day.
It's just a simple dandelion; yet I used three flash units to create the photograph:
I used the Nikon D800 camera and Nikon 200 f/4 Micro lens for this picture. The exposure is 5 seconds, f/20 at ISO 100. Given that the room was quite dark, any shutter speed faster than 10 seconds removes any trace of ambient light--leaving the flash units to provide the entire exposure. Of course, the camera/lens is secured to a stable tripod.
Changing the gel color of the background light quickly provides a different background color with very little effort:
But, I prefer the blue one as I think it looks more like the dandelion is being photographed in front of a clear, blue sky.