Hi Asher, good comments, you are right on British Racing Green.
This au is natural, no cloth. Taken outdoors. I noticed this clump of flowers in the front yard after taking a series of outdoor test shots with my then new 35L lens.
It is a backlit scene, and I used the adjustments in Lightroom/CS3 to darken the greenery around the yellow/red dappled flower, finished the leftovers with the burn tool. I wanted to project just a hint of the dark green broad leaves and the shape of the edge lines.
The green hue on the yellow petal edges is reflection from the dominant green surroundings. I purposely choose not to try and correct this, I feel it adds to the mood of the image.