Picotee Morning Glory

I am a fan of morning glories, and this one with the white edge is just perfect. I have 2 or 3 small plants that have volunteered from ones I grew in this spot last year. The foliage on these, both this year and last, is very light lime green. I wonder if they are growing in an exceptionally poor spot (I did fertilize them, though), or if this is the natural color of their foliage. I intend to collect some seed this year and plant them in a different spot next year to see what they do. I obtained these seed from a swap, and after a year, do not remember if there was a name attached or not. This is the beautiful blue color reminiscent of Heavenly Blue Morning Glory.
The beautiful pink and purple morning glories that grew in my daddy's corn field, and caused him much aggravation, were a form of bindweed, a term that most gardeners are familiar with. These were certainly perennial and were spread by plowing. The roots were broken into smaller pieces which then sprouted into more plants. Only the advent of herbicides brought some relief.
 There seems to be some disagreement about whether there are annual morning glories or not. The same plants seem to be called perennials in warmer climates and annuals in colder ones. To me this says they are perennial. A plant with roots that can reach a depth of 9 feet and regrow from those roots is surely perennial. So be forewarned, unless you want to keep the Round-Up handy, and you want to grow morning glories, perhaps the best thing to do is grow them in a pot with a saucer on the bottom to keep the roots from wandering, gather all the seed that forms, or grow them someplace where you don't care if they do take over.
 Aww, but they are sooo pretty!