Lilac shrubs often look quite ragged or unsightly by the end of summer as they prefer cooler climates than Maryland's and tend to contract some leaf-spot infections or stem-boring insect damage as they age. The photo files shared are too small for us to enlarge to see much detail, but the symptoms appear to be scorch in this case, which would mean the roots at some point were too dry or too wet. (Too wet is less likely since that usually results in root rot and more prominent leaf discoloration and branch dieback.)

While recent weather has been rainier for some areas in the state, in general, central Maryland is still in drought status since we remain several inches behind on typical rainfall totals. Monitoring plants for watering needs by feeling the soil moisture level and watering thoroughly when needed, important for both still-establishing plants as well as more mature specimens, will help them avoid the worst of drought stress. Nothing can reverse leaf damage after it occurs, at least until the plants leaf-out anew next spring, but as long as it doesn't worsen drastically, the plant will probably be fine. Lilacs have next year's flower buds already developed and dormant on the stems by this point (or if they don't yet, they will very soon), so avoiding too much drought stress will help them to keep those buds alive and healthy, since plants experiencing too much stress will sometimes abort flower buds in order to conserve resources.

Miri

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