There are people without a garden who love lilac. If they put their lilac in the same environment in which he should later grow permanently, he gets well. Potted plants can better cope with the life in the tub when the roots are used to the limited volume. In the case of lilac, this means logging sowing into the tub, because if you buy lilac, the one in the nursery has been repeatedly schooled in view of strong root development, in soil with lots of soil. This planting = transplanting also needs the bucket lilac, but directly from bucket to bucket, so that the root growth adapts to the earth volume.
Some of the lilac lovers are interested in bonsai and might be thrilled to learn that lilac is a great bonsai. Even as a noble Japanese Misho-Bonsai = from a seed starting attracted. The actual Bonsai-Beschnitt does not start until around three years, but during the rearing, the plant growth can be steered a bit towards "tiny" ...