I have two indian hawthorn plants. One blooms and one does not. Why is this?
Make sure your Indian Hawthorn is planted in full sun and has good air circulation around the plant.
Pruning should only be done after flowering.
You may want to do a soil test. Excess nitrogen can be the cause of lack of flowering. Over fertilizing with high nitrogen can also cause lots of lush greens and no flowers.
A phosphorous application can help promote flowering. Bone Meal is good organic application.