There are multiple reasons as to why your Azaleas might not be growing. The most obvious reason is pruning them incorrectly. The next common reason why Azaleas might not be blooming is there's too much nitrogen. So if you've applied fertilizers without getting the soil tested, then you have fed too much nitrogen. This can prevent Azaleas from blooming. Other reasons might be they're not receiving enough nutrients or water, the soil might be too alkaline. Or perhaps you've planted the wrong species of Azaleas.