In photography, “dynamic range” is the difference between the darkest and lightest tones in an image, generally pure black and pure white being the extremes.
Cameras have a narrower dynamic range than the human eye, although the gap is closing. The challenge photographing a wide dynamic range image like this one is to maintain details in the highlights (the sunset) without losing details in the shadows (the flowers), and vise versa. So, if I take a photo that is exposed to show details in the flowers, the sky would be virtually white. If I expose for the sky, the flowers are virtually black.
The solution is to use exposure blending, a post-processing technique used by photographers to combine multiple images into one using image editing software such as Adobe Photoshop. In this case, I took three photographs - the first to expose details in the flowers, the second to expose details in the trees, and the third to expose details in the sunset, and then blended the three images into one.