Graft lilacs in late winter, while stocks and scions are dormant. Completed grafts are packed in moist sand, moss, or sawdust, and stored in a cool place until planting in early spring. For forcing, growing in pots, or dwarfs, lilacs are budded on privet. Budding is done in August and September, with the shield bud method. The inserted buds remain dormant until the following spring when privet stocks are cut off just above the bud.
Growth is rapid, often two or three feet the first season.
Flower buds usually develop in the second season. The lilac, like many other shrubs, can be propagated by layering. This is a good method for the home gardener but too slow and cumbersome for mass production. Branches are brought down to the ground in spring and covered with soil, leaving only the tips above ground. Well-rooted plants may be obtained by this means in two seasons.