Allow it to soak in water, then add more rich loam to fill the hole. A mulch of leaves or straw three to four inches in depth during the first year is helpful in conserving moisture. Maintenance Lilacs require only moderate moisture and endure dry weather better than most shrubs. Do not overwater. They do not tolerate excessively wet or poorly drained soil.
Shallow cultivation keeps down weeds and unwanted root sprouts.
Multiple branching from the base permits removal of older stems that get too tall or are damaged by borers. Little pruning is needed the first three or four years. When branches begin to crowd, thin weak, interior growth moderately. Prune after flowers have fallen. Winter pruning destroys flower buds.