Unfortunately there are no herbicides that will kill morning glories but not your flowers--so your options are hand pulling, or if you don't like that then you can very carefully spray or paint Roundup or other herbicide of choice onto the plants, being careful to avoid the plants you don't want to kill. Painting herbicide onto weeds is effective in areas where there are a lot of other things growing, but unfortunately it's about as time-consuming as hand pulling.
I was afraid that would be the case. Curious as to whether they are sprouting from seed or existing roots already present. If from seeds, I wonder if pulling the existing ones and then using a preemergence herbicide like Preen would help.
Probably most of them are coming from seed, so a pre-emergent should stop new ones from coming up. Just make sure you reapply according to the directions on the package--it'll get washed out over time by watering/rain/etc.
Some Morning Glories are tuberous and sprout from the roots. The Bigroot Morning Glory (wild potato vine/Ipomoea pandurata) is a native wild perennial in most of North America (definitely in your Zone 6a) and can have 20-30lb roots several feel deep.
There are hundreds of species of MG and some are quite aggressive. You can either learn to love them, or get very familiar with a shovel.
I pull morning glories all summer long. The birds have planted them in my deciduous edge of forest. Then, they get deposited back into my garden. I haven't let any bloom in the landscaped area but one year-the first year I grew them. Sorry I ever got them started.
They aren't hard to pull up.
I FEEL YOUR PAIN..6 yrs ago we obtained a blueberry bush shrub as a gift, and along came the "mg" plants everywhere in my veggie garden...ever since im dealing with these vines pulling and pulling as I do not have a choice of putting any poison around my veggie garden area..so I am very familiar with the shovel, but mostly I pull by hand..not fun at all...
I used Preen on the ground around my gardens this year in April, and the morning glories are back, growing from seed the last of May. It seems the Preen did not last three months as they proclaim. I thought I had things pretty well taken care of, but when I came back from vacation, man, did I have the weeds! It's kind of discouraging. My hands ache from pulling so many weeds. Plus, it's getting hot and humid in my neck of the woods.
Thanks for the replies. I have them everywhere. In the veggie gardens, flower gardens, and the lawn. I've put 4 inches of mulch on the flower beds after pulling the weeds first, and they come up through the mulch. Ugh.
Morning glories are taking over our yard too. A friend actually gave me this plant without mentioning how invasive it is, so I planted it in what's turned out to be a horrific spot along the fence-line, close to my miniature roses. :( Next time someone offers me a morning glory, I will assume they hate me. LOL
I actually planted "Heavenly Blue" morning glory street side one year. When I redid that garden bed I found roots
deep into the earth. I couldn't dig deep enough to get all the roots. 5 years later I'm still getting runners.
I never let them grow more then a foot before I pull them and they haven't flowered for over 5 years but they're still coming.
I planted Morning Glories along a fence, and they reseeded themselves for over ten years. I've been pulling and digging up the seedlings for several years now. Are they sprouting from roots? They just keep coming all through the summer!
I am looking every day for morning glories in my veggie garden and so far no problem, where there used to be a huge problem. I do not know what I did to keep them away, but they will be back. Luciee (;^)
I finally got rid of mine (although my neighbor still has them pretty thick so I have to watch for them creeping under the fence) by deeply digging up my whole flower bed - about 1 foot deep - along that fenceline and taking out every even tiny bit of root I found. The roots travel, so instead of just tugging the root up, cutting it or anything else like that, I just gently followed the roots with my fingers through the dirt as far as I could. This is something that I have to monitor yearly, but I havent had to deep dig roots in years. The minute I see a leaf, I go after the root immediately. You have to be persistent!
I didn't know the MG had long roots. They get in my rose bushes and eek! they are hard to get out of there. Does round up work on them? You think you have them gone and then a month later, they are all over your shrubs again.
That's the strangest thing about the Heavenly Blue Morning Glories! I have never had a problem with them, even though they have grown steroidal for me by summer's end. The frost finally gets them and I pull them out. I have not had them grow back in four years of this steroidal growth. You must be "just lucky."
If you are speaking of wild morning glories, the white ones, bind weed, there is a mite that feeds off of the roots of the plant which extensions are offering for free if they are a serious problem in your area. The mite has yet to be proven to impact other morning glories. Do a search on bindweed mite in you area to see if they are offering the mites. I know they are in Colorado and Texas for sure.