Lilacs (Syringa spp.) thrive primarily in U.S. Department of Agriculture hardiness zones 4 through 7, although some varieties thrive in warmer zones 8 and 9. Most common lilacs require winter chill, but low-chill varieties like "Lavender Lady" thrive in mild winter areas. Too much water results in poor growth and flowering, and can also lead to rot problems. Planting in well-draining soil and in a sheltered area prevents water issues in areas with wet springs. Proper irrigation further ensures the plants produce their healthiest growth and ample spring flowers.
Cover the soil around the base of each lilac with a 2- to 3-inch layer of wood chip mulch. Keep the mulch 3 inches away from the base of the lilac trunk. Mulch helps the soil maintain a consistent level of moisture.
Water lilacs at the base of each plant. Avoid overhead watering during flowering, because wet blooms decline quickly or become prone to mildew problems.
Irrigate once every 10 to 14 days from spring until blooming ends. Supply 2 inches of water per plant, or enough to moisten the soil to a 12 inch depth. Lilacs respond best to deep, infrequent watering.
Reduce watering after flowering. Water only during extended dry periods when the top 3 inches of soil begins to dry completely. Lilacs also need watering if the leaves begin to visibly wilt during dry weather.
Things You Will Need
- Wood chip mulch
- Mulch requires annual reapplication to maintain its depth, because mulch naturally decomposes and breaks down.
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