I smelled the grandma of all our valerian plants one Saturday morning in late May. With a sweet vanilla fragrance that's strongest late in the afternoon, valerian (Valeriana officinalis) makes me happy to keep weeding until dark, just to be in her company. Valerian is so richly fragrant that some old timers call it garden heliotrope.
I love this stuff, and so do the cats. I often dig and dry several slightly stinky valerian roots to keep around as medicine -- outside, but out of the reach of cats and dogs. People take valerian to help with sleep, but for cats and dogs valerian is an enjoyable mind-altering drug. It turns out that valerian's calming effects travel Valium-like neural pathways in the brains of dogs, cats and people.
Yet the vanilla-musk fragrance of valerian takes it far beyond being a medicine-cabinet herb. A few stems in a vase will perfume a room. Indoors or out, fragrant valerian is always a sweet surprise.