The rose is a symbol of love, seems I remember that from childhood.  The rose was my mother's favorite flower....in times past, many people had rose gardens (I don't see those much anymore).  My mother had a rose garden, I grew up taking pictures of her roses.  Later, I learned that taking a picture of a rose can be so much more.  This picture shows the texture of the rose as well as filling the entire frame with the rose - it's one of my favorites.
 

This photo was taken with the Nikon Micro 105mm f/2.8 lens. ISO 200 (that's often my default ISO, although sometimes I use a lower value). Aperture (or f-stop) is f/22 to provide a larger amount of depth of field and get the majority of the rose in focus. The shutter speed is 6 seconds - yes, 6 seconds - make sure the rose is in a protected environment such that movement does not occur. In my case, this rose was cut and sitting in a vase.  A tripod and remote release (a cable release was used) is also very important to ensure clarity and sharpness.