Hi Lin,
I do not know if 'Alba' is a cultivar of C. montana or not, but you can go to the generic entry for C. montana
at the bottom of the page there is a link for "Add a new plant to the database"--click on that to propose the addition of the cultivar 'Alba'
I do know that C. montana 'Alba' would be smaller flowered, than the one in your picture posted here, and *white* if it exists...so if you are looking to add this plant in the image to your list, might I suggest that it belongs under a different classification?
