I have grown morning glories for about ten years and I never saved the seeds until this year. It's so easy that I'm actually embarrassed that I have never done it before. It only takes minutes and you can not only save enough for your containers next year, you will probably have plenty to give away. They would make great gifts.
My all time favorite morning glory is 'Grandpa Ott's,' with it's deep, velvety purple blossom with a luminous magenta throat. I can't get enough of them. I also love 'heavenly blue.' It is oddly old-fashioned and elegant, reminding me of grandmothers and lawn ornaments.
My only caution with morning glories is that in some areas they are considered an invasive and can self-seed like mad. They are illegal in Arizona.
There is a lot of confusion about morning glories because "field morning glory" also known as bindweed is hugely invasive. Bindweed is in the morning glory family and looks like a decorative morning glory, however it spreads quickly by rhizome and seed and can devastate natural areas and gardens by choking out other plants. Bindweed is Convolvulus arvensis L.
Decorative morning glories, Ipomoea purpurea, spread only by seed. In warmer climates even the decorative morning glories can be considered invasive.
To buy Grandpa Ott's Seeds from the granddaughter of Grandpa Ott.