Agastache is a genus of about 22 species of aromatic perennials in the mint family, most native to the grasslands, chaparral, and mountain meadows of North America, with a second group distributed across Asia. The genus name derives from ancient Greek meaning "very much" and "ear of grain," describing the dense upright flower spikes that characterize the group. Colors run from cool white through blue and purple to warm shades of red and orange depending on species, and the foliage releases a minty or anise-like fragrance when brushed.

Good drainage is the cardinal rule with hyssops — wet winter roots in heavy clay are reliably fatal, and plants in poorly drained ground often fail to return after their first season. Raised beds, containers, and slopes all suit them well. In full sun they bloom from midsummer through frost, attracting bees, butterflies, and hummingbirds in remarkable numbers. Cultivars like Blue Fortune, Blue Boa, and the Acapulco series have been selected for heat and humidity tolerance, making them well adapted to southeastern summers. Deer and rabbits largely leave them alone.