I've come to learn that lilacs are often planted near a farmhouse door for good luck, and because they offered beauty in the midst of challenge and hard work. Yep.
I've also read that many families planted lilacs in the late 1860s in memory of Abraham Lincoln, as eulogized in Walt Whitman's When Lilacs Last in the Dooryard Bloom'd. And because they are long-lived plants, you occasionally see a large bush near where a 19th-century farmhouse once stood.
Last spring, we planted four lilac bushes. Only two survived the deer and drought. But yesterday, my neighbor, Sandy, brought me a lilac shoot to transplant. I'll plant my gift near the two surviving bushes and hope that 100 years from now whomever is living in our old farmhouse will smell the blossoms and think of those who have gone before. (I'm also hoping that they grow and flower while I'm still around to enjoy them!)
In the door-yard fronting an old farm-house, near the white-wash’d palings,
Stands the lilac bush, tall-growing, with heart-shaped leaves of rich green,
With many a pointed blossom, rising, delicate, with the perfume strong I love,
With delicate-color’d blossoms, and heart-shaped leaves of rich green,
A sprig, with its flower, I break.
-- excerpt from When Lilacs Last in the Dooryard Bloom'd by Walt Whitman, 1865,