The answer to 'hedge not growing' is that there are several common causes, including improper soil conditions, lack of sunlight, pests or diseases, and improper pruning. Symptoms may include stunted growth, yellowing leaves, and uneven or patchy appearance. Solutions can include amending the soil, adjusting sunlight exposure, treating pests or diseases, and properly pruning the hedge.
If the hedge is not growing well despite your efforts, it's best to consult a professional landscaper or horticulturist. They can diagnose the specific issue and recommend the best course of action to get your hedge thriving again.