Lilacs are old-fashioned favorites of all landscapers and homeowners alike. Their dense, grape-like clusters of fragrant flowers in stunning colors of white, lavender or red. They tend to bloom in mid-spring, usually around mid-April to early May, right in time for Mother’s Day. Lilacs make attractive plants when mixing them in with other plants in a border, or even for informal hedges. Once well established, they are extremely drought resistant and keep their bright green foliage in the extreme summer heat.