How to Propagate Californian lilac 'A.T. Johnson'?
Propagate by semi-ripe cuttings in mid to late summer

Californian lilac 'A.T. Johnson' · Ceanothus 'A.T. Johnson'
Grow in fertile, well-drained soil in full sun with shelter from strong, cold winds. Lime tolerant but may become chlorotic on shallow chalk soils. See ceanothus cultivation
Propagate by semi-ripe cuttings in mid to late summer