Lilac (Syringa)

• Deciduous
• Climate zones vary
• Full sun or partial shade
• Regular watering

These multistemmed shrubs are cherished for the showy, usually fragrant flowers that cluster at their stem tips. While their foliage and overall appearance are somewhat less than striking, many gardeners consider the bland out-of-bloom looks a small price to pay for the blossoms. Be patient when you buy a lilac: plants usually don’t bloom until they reach 2 to 5 years old.

Lilacs do best in climates with winter chill, since they need cold to set blossoms. They prefer sun but need some shade where summers are hot. Give them regular water and well-drained, well-amended, neutral to slightly alkaline soil. If soil is acid, adjust the pH before planting.

Rejuvenate old, overgrown plants by cutting a few of the oldest stems to the ground each year. Prune to shape during bloom, cutting currently flowering or spent stems back to a main branch.

S. patula ‘Miss Kim’. Zones 1-9, 14-16, 32-43. Several smaller species lilacs are gaining popularity; S. patula ‘Miss Kim’ is one of the most widely grown. It stays at about 4 feet tall and 3 feet wide for many years. Flowers are pale lavender blue and very fragrant; dark green leaves turn purple in fall.

S. vulgaris. Zones 1-11, 14, 32-45. This species and its hybrids are among the most fragrant of all lilacs. The species eventually reaches a height of 20 feet, with nearly equal spread. Flowers are pinkish lavender, bluish lavender, or white. Over the years, many hundreds of varieties (often called French hybrids) have been developed from S. vulgaris; they vary in form and size and bear flowers in pink, lavender, purple, wine red, or white.

Note: If you live in a warm-winter climate and can’t get lilacs to bloom, choose one of the Descanso Hybrids of S. vulgaris. Developed in Southern California, these are especially well suited to winters with little or no frost.