The answer to 'shrub turning brown' is that there are several common causes, including drought stress, disease, pests, or improper planting or care. Symptoms may include leaves turning brown, wilting, or falling off. Solutions can include watering, pruning, applying fungicides or pesticides, or replanting the shrub in the right location and conditions.
It's important to diagnose the specific cause before taking action. If the problem persists or you're unsure of the cause, it's best to consult a professional landscaper or horticulturist who can assess the issue and recommend the appropriate treatment.