j_bis10,
Plastic surgeons usually recommend that scars not be exposed to sunlight for about one year. In the early stages of healing, if a scar is exposed to a lot of ultraviolet light, it will turn a dark brown color. Almost as if it gets extra tanned forever. And will always be a darker color than the surrounding tissue.
During the first year it is recommended that the scar be covered with a small bandage. But, as time progresses, it is then okay to go to a very high number sun block.
Since you are now a year out from your surgery, it is probably okay for it to be in the sun. If you are concerned, place a little sun block, in a stripe, just over the incision line.
(Of course, you know how plastic surgeons feel about tanning in general!)
Good luck.