Morning Gloried

Question: I am wondering why my morning glories don’t bloom. I get lush leaf growth but only a few, late blooms (none at all yet this year). They get plenty of sun and I don’t feed them.

responder: Carrie B. - UVM Extension Master Gardener Program  Replied September 03, 2024, 8:13 AM EDT
response: Hi Heidi, Thank you for reaching out to the helpline. In general when plants fail to bloom it is due  to these factors: age, temperature, pruning, nutrition and light. Some plants can also have an alternate flowering habit where they bloom great one year and don't the next.  With age, some plants will produce an abundance of leaf and stem growth in their juvenile stage, then flower later. Temperature can affect plants that require a certain cold or dormant period to bloom, or an unexpected frost can damage emerging buds. Improper pruning methods or timing could result in cutting off buds before flowering. The following two factors are pretty common and may be what's happening to your morning glories: The nutrient factor - Typically plants that are not blooming but have an abundance of healthy vegetative growth are getting too much nitrogen. Since you are not fertilizing, you may have a high nitrogen content or just very fertile soil. The light factor (Photoperiodism) - Photoperiodism in plants is the process by which plants use the length of light and darkness to regulate flowering & certain other processes, regardless of the ambient temperature or weather. Plants are categorized by Long-Day, Short-Day or Day-Neutral. Morning Glories are 'short-day' plants which means they may only bloom when the days are shorter (typically less than 10-12hrs of sunlight). I have heard of many cases where these plants may bloom in the spring (when the days are shorter) then loose their blooms during the long summer days. In the fall when the days begin to get shorter, they would bloom again. So, I wouldn't be surprised if you start to see blooms in the upcoming weeks until the weather changes. Here's a link that you might find helpful on this topic. Why Plants Fail to Bloom I hope this helps! If you have any other questions, don't hesitate to reach back out.

responder: The Question Asker Replied September 03, 2024, 8:23 AM EDT
response: Morning glories are annuals, so the age factor is not really an issue. I thought it might be due to the soil being too rich, so I tried them in a different location with poorer soil, but I got exactly the same results.I wonder if you can provide some information specific to morning glories.On Tue, Sep 3, 2024 at 8:13 AM Ask Extension <<personal data hidden>> wrote:

responder: An Ask Extension Expert Replied September 06, 2024, 9:13 AM EDT
response: Hi Heidi:  Carrie provided some information specific to Morning Glory and reasons why they are not blooming, i.e. the light factors, etc.  in her first reply to you. Please review that information.   There are not a lot of resources out there on Morning Glory, but here's some additional info.  Are the plants exposed to any kind of night light, such as  porch lights, street lights, automatic on/off lighting? This can affect the blooming stage. Some studies show that short day  plants will not flower if their night time darkness is broken by brief exposure to light at night. So, if your plants are receiving light from a porch lamp or street light, this could prevent or delay flowering.  Were they started indoors first, prior to planting outside? Some varieties take up to 120 days to mature. We don't have a long enough season in Vermont for them to mature before the day light hours start getting shorter.   Here is some information I found specific to growing morning glory:  How to grow annual morning glory: Choose a site that receives full sun and has well-draining soil. Annual morning glory also grows well in containers. Make sure there is a trellis or fence for the plants to climb. Annual morning glory vines can grow up to 15 feet long depending on the cultivar. Annual morning glory is a heat-loving plant, so wait until the soil warms up to at least 60 F. Then, plant the seeds directly in the soil about ¼” deep. Keep the soil moist. Once past the seedling stage, the plants tolerate dry soil but appreciate irrigation during heat waves. Cultivars of annual morning glory to try: Heavenly Blue (4- to 5-inch blue flowers) Scarlett O’Hara (4-inch red flowers) Flying Saucers (5- to 6-inch variegated blue and white flowers) Grandpa Ott’s (2- to 3-inch deep purple flowers with a red center) Zeeland Hybrid (mix of pink, purple, white, and variegated flowers) Follow the seed packet directions specific to the variety you are growing, start indoors (if days to flowering indicates 120 days) and then transplant when ground is 55-60 degrees.  Another resource provided the following, just another option:  Here is an idea from my personal experience—last year my Heavenly Blue m.g. began setting lots of flower buds in early October, just as night temperatures were about to fall so low as to kill them (light frost). Before that happened, I cut long vines full of buds off the main plant, brought them inside and placed them in a large vase of water, draping the vines over my plant stand in the kitchen patio door. They bloomed and I had beautiful m.g.s into early December!  If it's a nutrient balance issue, you could try growing them in pots using a potting soil that is low in nitrogen.  It may not be too late for your plants to bloom.   I hope this is helpful.