Caring for California Lilac

California lilac has low water needs once established and actually performs better with benign neglect than fussy attention. In the first growing season, water sparingly during dry spells—roughly once every two weeks if there's no rain—but avoid keeping the soil constantly moist. From the second year onwards, established plants rarely need watering except during severe summer drought. Overwatering, particularly in winter, is a common cause of failure; wet roots in cold weather often lead to fatal root rot. Feed sparingly in April with a light application of general-purpose granular fertiliser (such as blood, fish and bone) or a low-nitrogen feed. Too much fertiliser, especially nitrogen-rich types, produces lush soft growth that's prone to frost damage and reduces flowering. One feed per year is sufficient; avoid feeding after May. Mulch annually in spring with a 3–5 cm layer of gravel or grit around the base, keeping it clear of the stem. Avoid organic mulches like compost or bark, which retain moisture and can encourage collar rot. California lilac is generally pest-free but can occasionally suffer from scale insects or aphids on young growth; treat with horticultural soap if necessary. The main disease risk is honey fungus in poorly drained soils, which is usually fatal. Phytophthora root rot can also occur in waterlogged conditions—prevention through excellent drainage is essential. In colder zones (7a–7b), protect young plants with fleece during severe winter weather for the first two years. Established plants are tougher but may suffer dieback in harsh winters; prune out any dead wood in April. Avoid planting in frost pockets or exposed positions.