How to Grow Cardinal Climber Flowers (Ipomoea Sloteri)

by Matt Gibson

Horticulturists developed the cardinal climber flower to bloom profusely and climb swiftly during the summer months by crossing the cardinal vine and the morning glory flower, and the results are fantastic. This hybrid is an annual that produces bright red tubular flowers with yellow or white throats that bloom atop lacy fern-like blue-green foliage.

The flowers are very similar to the blooms of the morning glory flower. Five overlapping petals form a pentagon-like shape and flare up at the ends. Out of the center of the bloom, five stamens in shades of white to yellow protrude, inviting hummingbirds to feast during the day before closing up tightly at night. The foliage resembles the leaves of a palm tree, though of course it’s much smaller in size. This voracious vine grows well in almost every climate, attracts hummingbirds as well as some butterflies and bees, and can twine to reach heights of 10 to 20 feet.

The blooms open up, shine bright and then fall off the vine, so there’s no need to deadhead cardinal climber to encourage more blooms. In fact, more blooming is not even possible, as this plant produces more blooms during one season than many less industrious flowers will produce in an entire lifetime, and the immense amount of blooming makes the cardinal climber a wonderful addition to any summer garden. Cardinal climbers are also a great choice for any garden area that needs a more colorful wall, trellis, obelisk, or arbor, as this vine will add a vertical flair that will have your neighbors asking questions. Mainly, they’ll be asking for a cutting or wanting to know where can they get their own.

Varieties of Cardinal Climber Flowers

There is only one variety of the cardinal climber, which was bred as a cross between the cardinal vine and the red morning glory. However, there are over 100 different species in the ipomoea family, mostly consisting of different types and shades of the common morning glory flower.

Growing Conditions for Cardinal Climber

Cardinal climber is an annual that is frost tender. It prefers full sun to partial shade, and if given the right blend of sun and shade, it will provide its conscientious owners with even more flowers and a fuller, sturdier vine. The vine will grow and climb on anything it can, usually to at least 10 feet, but often stretching higher. Cardinal climber blooms from midsummer until the first frost in the fall.

Though cardinal climber is not particular about soil pH, the neutral range has shown the best results with this species. Use soil in the range of 6.0 to 7.2 for optimal growth, and don’t worry if your soil isn’t very rich in nutrients. A little bit of compost or organic material mixed into your growing soil will be all the food your climbers need to flourish all season long. Optimally, their soil will need to be well-drained and regularly watered. Though cardinals will tolerate dry soil, you’ll see much better results with regular watering.  

How to Plant Cardinal Climber

Plants in the morning glory family does not enjoy being transplanted, and the specimens rarely survive the process if it’s attempted. That’s why you’ll see it advised to directly sow most varieties. The seeds have a hard shell and must be scarified before they start the process of germination. Nick the seeds with a sharp knife, or use sandpaper to wear down the rough exterior. Then soak them in warm water the night before you’ll sow them. The seeds should reach germination within one to two weeks.

Starting cardinal climber seeds indoors is a tricky proposition, but the choice is yours. Just be forewarned that plants in the morning glory family, cardinal climbers included, don’t like having their roots disturbed. That’s why they are often directly sown into the ground after all danger of frost has passed. However, some gardeners with especially green thumbs have had success starting cardinal climber plants indoors, so we leave the decision up to you. Just be sure to wait until after the last frost has passed before moving your young plants outside, and try not to shock the roots too much during the transplant by keeping them in the same general form they took within their indoor planters, allowing them to spread out naturally on their own at their leisure after the move. If you’re starting cardinal climbers indoors, start the seeds about four to six weeks before the last frost of the season. Once that last frost has passed and your garden’s soil is warm to the touch, it’s the time to transplant—or preferably, to sow the seeds directly. Plant seeds about one-quarter inch deep, and space them out six to 12 inches apart. 

Care for Cardinal Climber

There is really not much care needed for cardinal climbers. Once you get them going, they only need occasional watering, whenever nature isn’t meeting their modest demands. You can decide whether or not to occasionally trim the vines. Trimming won’t hurt the plant or inhibit growth, but it isn’t necessary, either. There is no need to deadhead the blooms, as they will fall off naturally when the time is right, and new blooms will pop up in the place of the old ones. 

Ways to Use Cardinal Climber in Your Garden

As mentioned above, cardinal climbers are fantastic choices to add some color to a lonely wall, fence, or other vertical feature in your yard or garden, as they will literally climb anything you put in their path. If you have a wall that is lacking in color, cardinal climbers are the perfect solution. If climbers are not given a vertical support, they are also known to spread out horizontally, which gives you the freedom to use them either way you wish.

Do you have a bunch of low-lying fall flowers that are dormant during the summer season? If the answer is yes, you might try planting cardinal climbers at the edges of those garden beds. If the vines are not given a vertical surface, they will spread out horizontally and cover the dormant perennials so that your beds feature beautiful blooms all year long. As soon as the first frost hits, the cardinal climbers will give up the ghost, allowing next season’s plants to take over. You can then gently remove them from the beds to give your fall flowers room to shine.

Cardinal climbers also do very well in containers, but you will want to plant them by themselves, as they tend to overwhelm neighbors if they’re crammed too close together. If you are using ground containers, try giving your climbers some sort of stake as a support to climb on in order to give them some vertical room and add geometric variety to your garden. A hanging basket will have them cascading upward over the hanger attachment, then falling luxuriously downward toward the ground to create a pool of vibrant blooms.

Garden Pests and Diseases of Cardinal Climber

Though cardinal climbers have no significant disease or pest issues that target them, rabbits and deer may choose to chomp on your vines from time to time. If rabbits and deer are a problem in your area, you may want to plant your climbers out of reach, or put some obstacles in the path of any pesky perusers. Though these flowers are virtually pest-free, if the vines grow too thick, they can have an occasional issue with whiteflies. If you start to see their signs, insecticidal soap is an easy fix for the problem. 

Cardinal Climber for Indoor Bouquets

Cardinal climbers are not used for indoor bouquets, as the blooms do not last long after cuttings. In fact, the blooms don’t last long at all, whether you cut them or not. Instead, the productive plants just replenish their blossoms almost instantaneously. If you want to enjoy cardinal climbers indoors, just plant them in containers or hanging baskets inside your home, then make sure they get a good deal of morning sun everyday.

Two Notes of Caution

1. All parts of the cardinal climber are poisonous to humans, cats, and dogs if ingested, especially the seeds, so make sure you plant this species out of the reach of children and pets to avoid any mishaps.  
2.    In warmer climates, all members of the morning glory family, including cardinal climbers, are self-seeders. Though they are very rarely prolific enough to become a nuisance, one state, Arizona, has banned their sale due to their spreading tendencies. If cardinal climbers are not a problem in your area, feel free to allow your plants’ seeds to dry on the vine or where they fall, and collect them to replant next year. Climbers will not reseed in cold climate areas. If the climbers are sprouting up more than you want them to, simply pull up unwanted vines to thin the population.

Videos About Cardinal Climber

Check out this video for growing tips for cardinal climber: 

Check out this very cool six-day time lapse video of a cardinal climber vine growing and blooming:

Want to Learn More About Cardinal Climber?

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