Q.Morning Glories in a pot
Morning Glories in a pot are looking good on top but shabby in the lower stalks. I’ve trimmed the vines at the top to control growth and I’d hoped to bolster new growth so the potted vine would stay green and full from bottom to top. What can I do to generate growth in the lower part of the vine?

Keep the plant dead headed to encourage growth and keep it from putting energy into seeds.
Adequate water especially if the temperatures are above 85 degrees. You will need to water twice a day for these warm temperatures.
You could give it a light dose of fertilizer but look for a balanced fertilizer. 5-5-5 would be fine.
Here is a link to refresh you on the care.
https://www.gardeningknowhow.com/ornamental/vines/morning-glory/growing-morning-glories.htm