Lilac buds are already to open up which means that spring is really here.
...The lilac-scent, the bushes with dark green heart-shaped leaves,
Wood-violets, the little delicate pale blossoms called innocence,
Samples and sorts not for themselves alone, but for their atmosphere,
To grace the bush I love—to sing with the birds,
A warble for joy of lilac-time, returning in reminiscence.
Walt Whitman