Hi, Well my guess is that you have a bindweed problem. Bindweed looks like morning glory and is related, but although domestic morning glory does spread, it's not that hard to get rid of. Bindweed, however, (it has a white flower and looks like morning glory) can be a nightmare. I have it on my farm and I pull it when I see it and hoe it when it's thick. Otherwise, mulching your garden helps keep it in check, but all you can really do is keep it from setting seed and pulling them as they appear. It's not fun, but spraying herbicide doesn't help much because the plants appear randomly throughout the garden.