I've had the same experience as DonDuck reports, above. Morning Glories are beautiful at first but they're THUGS in a vegetable garden.
About 15 years ago I planted a pack of Heavenly Blue M.G. seeds and let them grow up my garden fence - they were really pretty. But, they've come up in that garden ever since as invasive, unattractive vines, and I can't get rid of them
The blossoms have bred back to tiny red things, and I don't think the vines are propagating from seeds, as for years I have removed all blossoms as they appear and the vines grow anyway. I think the M.G. plants grow from very deep thin roots that overwinter in the soil and can't be pulled out - they just break off if you try, and they come right back if they're sprayed with herbicide.
The only good thing about it is that as unwanted, impossible to get rid of weeds, they're not too bad. I've just learned to put up with the vines growing up and all through my tomato, pepper, and other plants.
I'm moving my vegetable garden to a new location and going to raised beds this year, and the Morning Glory infestation is one of the reasons I'm doing that.
