Japanese Lilac

• The Japanese lilac (Syringa reticulate) is hardy in USDA Hardiness Zones 3 to 7. The heart-shaped leaves of the Japanese lilac tree are deciduous and dark green. The tree produces white flowers that appear in early summer. Japanese lilac trees grow to heights reaching 25 feet with a spread of 15 to 25 feet. The root system of the lilac tree is shallow and is easily damaged by strong winds. When the Japanese lilac has wind damage, it can take two to three years for the tree to flower again.
  
  

Chinese Lilac

• The Chinese lilac tree (Syringa) has lavender flowers with a slight pinkish hue that appear in early May. The lilac tree reaches heights up to 12 feet with a spread of 12 feet. Flowers range in size from 4 to 6 inches long and last for about two weeks. The Chinese lilac is hardy in USDA Hardiness Zones 3 through 7.
  
  

Common Lilac

• Common lilac (Syringa vulgaris) grows to heights of 8 to 10 feet with a spread of 8 to 10 feet when mature. Whitish to purple fragrant flowers appear in late spring. The common lilac has an irregular shape with leggy branches sprouting out everywhere. Dark-green leaves on the common lilac tree grow from 2 to 5 inches long and up to 3 inches wide.
  
  

Persian Lilac

• Persian lilac (Syringa x persica) can be invasive if the growth is not controlled with pruning. Persian lilac trees attract birds, butterflies and bees with their fragrant lavender or violet flowers, which appear in late spring. The light-green leaves of the deciduous tree reach lengths up to 2 feet. Persian lilac trees reach heights of 4 to 8 feet. Any damage to the root system will cause the lilac tree not to flower for as long as three years. The Persian lilac tree is hardy in USDA Hardiness Zones 3 through 7. Seeds of the lilac tree are poisonous if ingested by people.