Probably the most common plants used in planters in the Chicago area has to be these ornamental sweet potato vines. You can find the chartreuse colored vine and this darker form growing in all parts of the city in the planters the city maintains. They spill over planters or are used as ground covers to great effect. My favorite is the two common ones you see is "blackie" even though it has a politically incorrect common name I love the dark foliage. I have one planted with my "black" calla lily and oxalis.
A couple of days ago I was out in the garden earlier than usual and was surprised to see the one that was potted was blooming. For years I've admired this plant but I don't recall ever seeing it bloom. If the flower of this sweet potato vine reminds you of a morning glory it is because they are in the same family.
From what I've read it is unusual for the flower to produce fruit or seeds so propagation is usually done by lifting the tuber (that is produced below ground) or by taking cuttings and keeping them in a bright light indoors over the winter. One website I read said that some people will bring the plant indoors and grow it as a houseplant for the winter and bring it out in the spring. I don't know if I'm going to try that because if the spiders and spider mites that flock to these plants outdoors are any indication of what is going to happen indoors I don't want to risk it.