The common lilac (Syringa vulgaris) grows 12 to 15 feet tall and 10 to 12 feet wide. There are many smaller dwarf varieties that mature at 4 to 6 feet tall and 3 to 7 feet wide. Japanese tree lilacs (Syringa reticulata) can reach 25 to 30 feet tall.

How much space does a lilac bush need?

Here’s the first rule of planting: lilacs need lots of space to grow. If you’re planting a hedge, they’ll need a spot at least seven to eight feet wide and ten feet wide for a shrub. They also need at least six hours of sun a day to have excellent flowering. Provide a well-drained, alkaline soil.

Where is the best place to plant a lilac bush?

Where to Plant Lilacs. The ideal spot to plant lilacs is in an area with full sun (at least 6 to 8 hours per day)—give them too much shade and they may not bloom. Lilacs also like slightly alkaline, moist, well-drained soil.