Grow the morning glory in full sun. The vine won't flower in the shade.
Change your watering schedule. If you water frequently, allow the soil to dry before watering again.
Avoid adding fertilizer. When a plant isn't responding as it should, many gardeners immediately grab the fertilizer bag. Morning glories do not require fertilizer, and will not flower with too much nitrogen in the soil.
Prune 1/2 inch off the tips of new shoots. This encourages the morning glory to produce new shoots -- and, consequently, new buds.