The answer to 'hedge yellowing' is that there are several common causes, including nutrient deficiencies, disease, pests, and environmental stress. Symptoms can include leaves turning yellow, wilting, and dropping prematurely. Solutions may involve fertilizing, pruning, treating pests or disease, or adjusting growing conditions.
In many cases, minor hedge yellowing can be addressed through DIY care like applying fertilizer or adjusting watering. However, if the issue persists or worsens, it's best to consult a professional landscaper who can properly diagnose the problem and recommend the appropriate treatment.