Answer: A reddish tint to the leaves is almost always environmental, so I don't think you're going to lose your lilac. It could be sunburn (did you move it to a sunnier spot?) or it could be a reaction to a cold snap in late spring, which is only showing up now. As long as the shrub looks otherwise healthy, I wouldn't be too concerned about the reddish colored leaves. Lilacs are sturdy plants and aside from watering them deeply when the soil begins to dry, they don't need any particular care. They won't need fertilizer (nitrogen can encourage lush, green growth at the expense of flowers), but they do appreciate growing in slightly alkaline soils. I suspect your soil is on the acidic side (areas of high rainfall generally are). You can work some lime or superphosphate into the soil over the roots of your lilac to help sweeten the soil. Best wishes with your lilac!
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