Answer: In general, fertilizing will not help a plant that is suffering unless the problem is nutrient based. This does not sound like something fertilizer would help. Unfortunately, lilacs are subject to several problems that could cause them to brown and based on your description I can't make a definite diagnosis. You might want to consult with your county extension horticulture staff (475-2200) for a specific diagnosis and suggested remedies. I'm really sorry I can't be more helpful.
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