Caren White is a Master Gardener and instructor at Home Gardeners School. She has been associated with Rutgers Gardens for over a decade.
One thing that I look forward to in the summer is being greeted by a profusion of morning glory flowers as I leave for work. I deliberately plant them along the fence at the end of my driveway so that I have a cheerful sendoff each day until the frost in the fall. My favorite are the classic Heavenly Blue morning glories.
What are Morning Glories?
Morning glories are annual vines that grow from 5 to 15 feet in length. The leaves are dark green and shaped like hearts. The flowers are trumpet shaped. They open in the morning and close in the afternoon. Each flower only lasts for a day. The flowers come in a range of colors. The classic is bright blue, but they can also be red, pink, white, purple and bicolor. The flowers are a magnet for butterflies and hummingbirds.
Morning glories readily self-seed in your garden. They can become invasive so many community gardens ban them. Some states ban them also. When that is the case, seed catalogs will note that the seeds cannot be shipped to those states.
Why are They Called Morning Glories?
Morning glory flowers open in the morning and close in the afternoon. However, if the vines are planted in a location that the sun does not reach until the afternoon, the flowers will open in the afternoon instead of the morning. I have noticed that on cloudy days, the flowers will either not open at all or if it is light enough, they will stay open all day.
Are Moon Flowers the Same as Morning Glories?
Moon flowers are related to morning glories. There are some key differences. Moon flowers open in the afternoon instead of the morning. They stay open through early evening and their white color appears to glow in the darkness. The flowers have a strong but pleasant fragrance. The flowers only come in white unlike morning glories which come in different colors including white.
Are Sweet Potato Vines the Same as Morning Glories?
Sweet potatoes are also related to morning glories. Their flowers and leaves are similar in appearance. The biggest difference between sweet potatoes and morning glories are the tubers produced by sweet potatoes. Morning glories do not produce tubers. Be aware that not all sweet potatoes are edible. The ornamental sweet potato vines that are grown for their foliage produce tubers that are not considered edible because of their terrible flavor. They are not poisonous. They just don’t taste like sweet potatoes.
How do Morning Glories Climb?
Morning glories climb using tendrils which twine around just about anything. Most gardeners provide supports for their vines such are trellis, tepees, fences and pergolas. The vines will even climb string. In my own garden, morning glories climbed my butterfly bush.
The vines grow and climb rapidly and can cover fences or even the walls of buildings if they have trellises. Many people use morning glories growing on fences to screen air conditioning units or garbage cans. If the vines do not have support in the vicinity, they will grow along the ground, twining around other plants and each other.
How to Germinate Morning Glory Seeds
Growing morning glories from seed is easy if you know the secret to getting the seed to germinate. The seeds have a hard covering that prevents them from germinating if you just plant them in the ground. You have to soften the hard covering. Most people nick the covering using something like nail clippers and then soak the seeds overnight. Other people use sand paper to wear down the covering before soaking the seeds overnight. Personally, I just soak the seeds overnight. That softens the hard seed coat so much that when I go to plant them the next day, some of the seeds have already germinated.
So what’s the best way to soak the seeds? Most people use wet paper towels. They moisten the paper towels and wrap the seeds in it. I’m a fan of reduce, reuse, recycle so I try to avoid using disposable items like paper towels. I use teacups instead. I partially fill a teacup with water and then drop the seeds in. Because I have cats that like to drink out of anything that has water in it, I cover the teacups with saucers. If I am soaking more than one kind of seed, I place the empty seed packet under the teacup and saucer to identify the seeds that are soaking in each cup.
How to Plant Morning Glory Seeds
If you live in a northern climate or you want flowers are soon as possible, you may want to start your seeds indoors 4 to 6 weeks before your last frost date. Most of us direct sow our seeds in the spring after our last frost when the soil has warmed to at least 60⁰F. Choose a spot with well-drained soil that gets full sun which means 6 to 8 hours of direct sun every day. Plant the seeds ¼ inch deep and 6 inches apart. Keep the soil moist until your seeds sprout. After that, you can cut back on watering your plants to just 1 inch a week. A thick layer of mulch will help the soil retain water so that it doesn’t dry out between waterings.
Fertilize your vines every 4 to 5 weeks with a low nitrogen, high phosphorous fertilizer. Too much nitrogen will result in all foliage and no flowers. The vines will produce flowers all summer whether you deadhead them or not. You might want to deadhead the flowers to prevent the vines from producing seed that will result in a bumper crop of morning glories next year. The seeds are easy to harvest if you would like to save some of the seed for next year.
How to Prevent Pests From Eating Morning Glory Vines
Morning glories are pretty much disease resistant. They aren’t bothered by insects either. It’s four legged pests that can cause the most damage. Deer, rabbits and ground hogs all find morning glory vines delicious. To prevent them from eating your vines, place a 3 to 5 foot fence around your vines. As the vines grow, they will grow through the fence so that it will no longer be seen. At this point, the vines will be long enough that if a hungry deer or other pest starts nibbling, it won’t kill the vines.
Questions & Answers
Question: Why do my Morning Glories never get large flowers, just small tiny ones?
Answer: There are a number of flowering vines that resemble morning glories but are not actually morning glories. They have much smaller flowers. You are probably growing one of those. Morning glories are very easy to grow from seed so I would recommend that you purchase a packet of morning glory seeds in the spring to plant. Be sure to soak them overnight to soften the seed coat. Then you can plant them directly into your garden.
Question: Do morning glories need to be cut back after frost?
Answer: Morning glories will die after the frost. All dead plant material should be removed from your garden. Harmful insects use the debris to hibernate in over the winter and emerge the following spring to destroy your garden so don't give them any place to hibernate. Get rid of everything.
Question: My morning glory forms buds and they come out to proper size but they won't open? Any idea why, please?
Answer: Are your vines getting enough sunlight? Morning glories need full sun which is at least 6 to 8 hours per day. I have tried growing morning glories in partial shade and got short vines with very few flowers. Or perhaps you are not looking at your vines at the correct time of day. The flowers open very early in the morning and then close by late morning. I plant my vines along the fence at the end of my driveway so that I see the flowers every morning before I leave for work. The flowers are closed when I get home from work.
Question: I have what I think is a healthy morning glory plant but no flowers. What is wrong?
Answer: Your vine is probably not getting enough sun. Morning glories grow best in full sun which means a minimum of 6 to 8 hours of sunlight every day. If they only get morning sun or afternoon sun, that is not enough. I have tried to grow them in partial shade (morning sun only) and the vines were short with very few flowers. Also remember that morning glories only bloom in the morning. If you are looking at your vines in the afternoon, there will be no blooms. So check them out first thing in the morning to see if they are blooming.
© 2018 Caren White
Caren White (author) on May 29, 2020:
Soaking the seeds or nicking them just hastens germination.
Tom J. on May 28, 2020:
I have been growing Morning Glories for years and never once nicked the seed or soaked them first. Just plant them to the proper depth, keep them moist and they will sprout in a week as long as it is warm...70's plus
Caren White (author) on July 07, 2019:
Two things come immediately to mind: sunlight and fertilizer. Morning glories need full sun which means 6 to 8 hours of sunlight every day. Just morning sunlight or just afternoon sunlight is not enough. They need sunlight all day. The other culprit could be the type of fertilizer that you are using. Morning gloiries need a low nitrogen - high phosphorous fertilizer to bloom their best. Too much nitrogen will result in foliage, but no flowers.
Diana Grant from United Kingdom on July 06, 2019:
I love morning glories and have planted seeds for several years running, but get very poor results. Usually not one of them flowers and the plants just wilt and die. I live in the UK, plant them in large pots or troughs with trellis, in a sunny position in potting compost and water them, but I must still be doing something wrong.
Have you got any advice please?
Dianna Mendez on July 26, 2018:
I have not seen many of these pretty flowers here in South Florida. They are favorites in the midwest where I grew up as a child. I think it is fascinating that they will bloom in the afternoon as well.
Caren White (author) on July 06, 2018:
Barbara, try fencing around the bottoms of your vines.
Caren White (author) on July 06, 2018:
That's the best thing about gardening - there is always next year.
Jo Miller from Tennessee on July 06, 2018:
I usually have morning glories and moon flowers growing on my screened in back porch, but forgot to get them started. It's a little late now, but there's always next year.
Caren White (author) on June 29, 2018:
Mary, you can grow morning glories in containers provided you give them something to climb on.
Mary Norton from Ontario, Canada on June 29, 2018:
I love morning glories and we used to plant them every year. Now, we stick largely to potted plants but I still want to do so. They perk you up.
Caren White (author) on June 28, 2018:
Try a fence around them to prevent the deer, rabbits and ground hogs from eating the vines.
Barbara Badder from USA on June 28, 2018:
We grow morning glories every year. They are beautiful. The area we live in now has lots of deer, rabbits and ground hogs. I'll have to figure out how to keep them away.