Why Is My Morning Glory Turning Yellow. I have seen this happen when Morning Glory vines found their way into a house and grew up to the window. Maybe others can give you some good advice.
By chance I found an old Martha Stewart magazine yesterday and the main thing in it is morning glories. 26042021 Too rich of a soil is often the reason for a morning glory not blooming as rich or over-fertilized soil produces lush beautiful foliage at the expense of blooms. They suck on the plant juices removing chlorophyll and injecting toxins which cause white dots on the foliage.
The primary cause of leaf scorch is the plants inability to draw up.
The same phenomina has occured on some of my Morning Glory in the past. A disease that can also affect morning glory leaves is called canker. They may be red black brown or yellow. If you find it present and if the soil hasnt been soggy through the winer and spring it may be a fungal disease that attacks the roots.