to me it looks like exposure :)

Sabrina,

Well, here's my Exposure if it helps:

and here is my Summertime:

Here is Pink Diamond...

Thank you both. It is a deep pink and not the lighter pink of your blooms.

Pink diamond seems to be close to the color. Since once the patent expires they can be renamed how do you keep track of the cultivars ?

I guess sun exposure aso also have a lot to do, mu exposure didn't get the light i would have liked it to, this was it's second year with me

and tis was last year

there are so many similar ones... now i'm doubting what it might be too! lol

Well Ladies, Pink Diamond is a more saturated pink than my picture depicts, I happened to show one of the lighter ones. Here is one that is more realistic but it has a red ring in the throat which yours doesn't appear to have but depending on the depth of color of the Pink Diamond, It can be hardly noticeable. So it probably is something else all together as yours doesn't appear to have the red ring.

I guess it's time for someone else to come up with a theory....☺☺ Sorry I couldn't crack this mystery.:-))

Is it possible there would be some variation between one growing indoors and another growing outside for many years ? Next time when it blooms I will keep this ring in mind.

The texture of the flower and pink pistil/stamen seem to indicate that Pink Diamond is a possibility.