Morning glory is one of those magical plants that can transform a boring fence into a something far more interacting overnight. Well, not literally overnight – but these fast-growing vines sure make it feel that way! I planted some last spring and practically watched them climb before my eyes.
But morning glories are actually pretty picky about their neighbors. Some plants just don’t mix well with these climbers & I learned that the hard way when my carefully planned garden corner turned into a disaster zone.
Let me take you through which plants to keep far away from your morning glory vines and why. Your garden (and your sanity) will thank you.
Understanding Morning Glory
First things first – morning glories aren’t just pretty faces. They can grow up to 10 feet in a single season, with some varieties stretching to 15 feet or more! They’re dreamboats for covering unsightly walls, fences,l or creating natural privacy screens. And those trumpet-shaped flowers that come in blues, purples, pinks and whites? Absolute showstoppers.
But beneath that gorgeous exterior lies a bit of a garden bully. Morning glories are extremely competitive plants. They fight for sunlight, soil nutrients and space like they’re in some kind of botanical championship. Their sprawling root systems and fast-growing vines can quickly overwhelm neighboring plants.
I remember planting some blue morning glories next to my tomatoes one year, thinking they’d make a pretty backdrop. They didn’t! The morning glory vines wrapped themselves around my tomato plants like they were giving them a not-so-friendly hug. By mid-summer my tomatoes were struggling to breathe while the morning glories partied on.
That’s why companion planting with morning glory requires some strategy. Get it wrong & you’ll end up with either stressed-out morning glories or casualties among your other plants (usually both). Morning glories can also self-seed prolifically, meaning they might show up in places you never intended the following year.
So lets go through which plants should definitely keep their distance from your morning glory vines.
13 Plants That Hate Being Near Morning Glory
1. Tomatoes
My personal garden disaster taught me this one the hard way. Morning glories and tomatoes are terrible companions. The vines will literally strangle your tomato plants while competing for the same nutrients. Plus morning glories can actually stunt tomato growth by releasing chemicals that tomatoes just don’t appreciate.
When I finally untangled my poor tomato plants their stems were damaged and production dropped noticeably. Not worth the pretty blue flowers, I promise you.
2. Potatoes
Like their tomato cousins, potatoes & morning glories are a match made in garden hell. Morning glory’s aggressive vines can completely overwhelm potato plants. And both plants are hungry for potassium, creating an underground nutrient battle you don’t want in your garden.
3. Beans
This pairing seems logical at first – both are climbers, right? But that’s exactly the problem. Plant morning glories near beans and you’ll have a tangled mess faster than you can say “garden disaster.”
The morning glory vines will wrap around bean plants, making harvesting nearly impossible. As well though beans fix nitrogen in the soil (usually a good thing), but morning glories prefer soil that’s not too nitrogen-rich for best flowering.
4. Sweet Potatoes
Here’s a surprise – morning glories and sweet potatoes are actually related. They’re in the same plant family (Convolvulaceae), which means they’re susceptible to many of the same pests and diseases. Plant them together and you’re creating a pest buffet.
I’ve also found that sweet potatoes never reach their full size when planted near morning glories. The competition for underground space is just too intense.
5. Peppers
Peppers need their space and don’t appreciate the shade that morning glory vines inevitably cast. The morning glory’s extensive root system also competes with pepper plants for water, leaving them perpetually thirsty.
6. Melons and Squash
Melons & squash plants spread horizontally across the ground, while morning glories reach for the sky. Sounds complementary, right? Wrong. The spreading habit of melons and squash actually creates the perfect highway for morning glory vines to travel across your garden.
Before you know it you’ll have morning glories popping up everywhere, and their roots will compete with your melons for nutrients. The vines can also block critical sunlight from reaching your melon and squash leaves.
7. Corn
I’ve seen websites suggest growing morning glories up cornstalks. Please don’t. While it looks picturesque, corn needs all its energy to produce those juicy ears. Morning glory vines will only stress the corn plants and potentially reduce your harvest.
Corn is also a heavy nitrogen feeder, while too much nitrogen causes morning glories to grow lush foliage at the expense of flowers. Nobody wins in this scenario.
8. Blackberries and Raspberries
Morning glories and berry bushes create a maintenance nightmare. The morning glory vines will weave themselves through the berry canes, making it nearly impossible to prune or harvest without damaging one or both plants.
9. Grapes
Similar to berries, grape vines & morning glories create a tangled mess that’s nearly impossible to sort out. Both are vigorous climbers competing for the same space and resources. The morning glory vines can actually strangle young grape vines if left unchecked.
On top of all that many of the trellises and supports used for grapes aren’t sturdy enough to handle the additional weight of morning glory vines.
10. Sunflowers
Sunflowers might seem like perfect supports for morning glories but this combination causes problems. Morning glory vines can actually restrict sunflower growth, while the dense shade from mature sunflower heads can prevent morning glories from receiving the full sun they need to flower properly.
11. Root Vegetables (Carrots, Radishes, Beets)
Morning glory’s extensive root system competes directly with root vegetables. Your carrots, radishes, beets etc. will end up stunted or deformed when they have to fight morning glory roots for space.
I once planted morning glories near my carrot bed and I ended up with the strangest looking, twisted carrots I’ve ever seen. The morning glory roots had pushed them aside as they grew.
12. Lettuce and Leafy Greens
Most leafy greens need good air circulation to prevent disease issues. Morning glory vines create the opposite – a humid, crowded environment perfect for fungal problems. Plus, as the vines grow, they’ll eventually shade your sun-loving greens too much.
13. Other Vining Plants (Cucumbers, Peas)
This one’s pretty obvious, but worth mentioning. Planting morning glories with other vining plants creates competition for climbing space. The more aggressive plant (usually the morning glory) will win, leaving you with strangled cucumber or pea vines.
Good Companion Plants for Morning Glory
Not all is lost though. Morning glories can play nice with certain plants. Here are some good companions:
- Zinnias – Their bright colors complement morning glories and they don’t compete for the same space
- Marigolds – These pest-repelling flowers can help protect morning glories from certain insects
- Ornamental grasses – These provide textural contrast without competing for nutrients
- Petunias – Low-growing and compatible with morning glories’ water needs
- Nasturtiums – Another trailing flower that stays low while morning glories climb
I’ve had great success with a morning glory/zinnia combination along my fence. The zinnias bloom during the day while morning glories take the morning shift, giving me constant color.
Tips for Successful Companion Planting with Morning Glories
- Always provide sturdy supports for morning glories to climb – this helps keep them from reaching for your other plants
- Consider planting morning glories in large containers with trellises to contain their spreading habit
- Plant companion flowers at least 12 inches away from morning glory roots
- Deadhead spent morning glory blooms regularly to prevent excessive self-seeding
- Apply mulch between morning glories and companions to help keep roots from competing
One trick I’ve found helpful is planting morning glories on the north side of other plants when possible. This prevents them from casting shade on sun-loving companions as they climb.
Final Thoughts
Morning glories are breathtaking plants. They’re perfect for covering unsightly areas or creating living screens. But they’re also garden bullies that need to be managed thoughtfully.
The main takeaway? Keep them away from vegetables, other vines and any plants you don’t want strangled by enthusiastic climbers.
Instead, pair them with compatible flowers like zinnias and marigolds. Or just give them their own dedicated space to climb and sprawl. A morning glory in the right spot with the right companions will reward you with a stunning display that makes all the planning worthwhile.
Gardening is always an experiment though. If you try a combination I’ve advised against and it works in your garden, that’s fantastic! Your specific soil, climate and garden conditions might create different results. The joy of gardening is discovering what works for you.