Applying proper herbicides in the late winter and early spring is a good first approach. Healthy smother crops like turf and other dense grasses can prevent Morning Glory Weed from growing, as can proper shade and watering. Remember, the healthier your lawn is, the less likely you are to see signs of any weeds at all.

Morning glories do best in soil that is moist but well-draining. A neutral soil pH of 6.0 to 6.8 is best, but morning glories will grow just about anywhere. However, they do bloom better in soil that is not too rich in organic matter. You can always amend the soil later if the vines look like they are struggling.

It is very difficult to kill morning glory and you need to be vigilant over a long period to completely eradicate it. As you have found, just spraying something like Roundup probably won't work.

Morning glories are low maintenance; just be sure to water during particularly dry periods. Mulch to retain moisture and suppress weeds. If you don't want the plant to reseed itself, pinch off old flowers before they turn into seedpods. This can also encourage the plant to keep producing more flowers.