The morning glory, Ipomoea purpurea, is an annual for cultivation in Zones 2 to 11 with funnel-like blue, pink, purple, white, or bicolor blossoms that adorn clinging vines from summer through fall.
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Our guide to growing morning glories provides all you need to know to grow and care for these flowering vines at your house.
The focus of this article is seven common causes of a failure to bloom and how to avoid them.
Here’s the lineup:
Reasons Why Morning Glory May Fail to Bloom
Let’s jump right in and get this problem solved.
Black rot and rust are two common diseases that may adversely affect morning glory blooms.
Inhibit both by sowing seeds in well-draining soil. Space them per seed packet directions to accommodate mature dimensions and facilitate airflow.
An excellent way to do this is to train each seedling to grow up a string attached to a fence or another structure you want it to climb. Mature vines benefit from periodic untangling and redirecting as needed.
Avoid under- and overwatering, as both render plants vulnerable to disease.
2. Hungry Herbivores
One reason you may not see flowers is that hungry wildlife may have eaten them before you look out in the morning.
I couldn’t believe it when I spotted one of the local groundhogs clinging to a chain-link fence and munching away on the vines intertwined in it.
And if you have a hairdresser friend, ask for some sweepings to sprinkle around the plants to dissuade nibblers with human scent.
3. Inadequate Sunlight
These early bloomers grow best in full sun, where fresh buds open and flower each morning. They live for one day, and the next morning, there is a new batch.
Plants in shady placements do not perform as well as those in full sun and are likely to produce fewer flowers.
When scouting garden sites, look for those that receive at least six hours of sunlight daily for the best outcome.
4. Moisture Stress
When plants don’t receive the proper amount of water, the foliage may turn yellow. This cautionary color is often confusing, as it may indicate overwatering or underwatering.
Flora suffering from moisture stress directs its energy toward survival, slowing vegetative and reproductive growth. Such energy-saving measures may reduce flower production.
Evaluate the recent weather and your watering habits to determine probable causes. Adjust watering as needed to provide one inch per week, including rain.
If oversaturation is a problem, consider mixing some horticultural grade sand into the garden soil per package instructions to improve drainage if it’s an ongoing issue.
5. Organically-Rich Soil
I. purpurea prefers poor soil. Under fertile conditions, plants are likely to produce an excess of lush foliage and few to no flowers.
An overabundance of leaves may be especially problematic when plants are fertilized with nitrogen-rich products that promote foliar growth.
Avoid pampering. Choose hardscrabble locations where the soil is not rich and loamy, and skip the fertilizer.
And while they generally feed on foliage, these pests may also damage buds and blooms – especially in the case of a severe infestation.
In addition, when under stress from insects, plants may slow their growth in an attempt to survive.
If you see aphids, dislodge them with a strong spray of water from the hose.
Handpick Japanese beetles and destroy them by crushing or dropping them into a pail of soapy water.
You may need to use an insecticide for persistent aphids, leaf miners, and spider mites. Organic neem oil is an excellent choice.
You can pick up Bonide Neem Oil from Arbico Organics.
To avoid pests, keep the garden weeded, try not to under- or overwater, and space plants generously for good airflow.
7. Self-Sown Progeny
I. purpurea is a robust self-sower. In my growing zone, the seeds that self-sow will winter over and sprout the following year.
Fresh seeds from a reputable seller offer the best opportunity for high-volume blooming. Those that sprout via self-sowing may be less vigorous, producing sparse foliage and flowers.
The pink ones in the photo above were the progeny of the progeny of a family member’s harvested seeds. And while they produced flowers, the blooms were less plentiful each successive year.
Glorious in Bloom
With these seven common causes for bloom failure in mind and armed with avoidance measures, it’s time to grow the morning glories of your dreams.
Why not make the most of their ability to turn backyard eyesores into flower-laden focal points by masking them with a profusion of blossoms from summer through fall?
When growing I. purpurea, please note that it can become invasive. To limit self-sowing, pick and discard seed pods when they are green and use a hoe to churn up and dispose of unwanted seedlings in early spring.
In addition, the seeds are toxic, so do not consume them under any circumstances.
What will it be? Blue, pink, purple, white, or a bicolor combination? Let us know in the comments section below! Whatever you choose, a glorious display awaits.
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