Anise Hyssop

Agastache foeniculum

Anise Hyssop (Agastache foeniculum) is a native perennial mint with square stems, leaves that are whitish underneath and smell of licorice when crushed, and dense spikes of small blue-violet flowers at the stem tips. It blooms from July into early September, and in the Black Hills it grows mostly in moist gulches and stream bottoms of the northern and central Hills.

Free photos from other sources

Anise Hyssop: Dense blue-violet flower spike, close up — Anise hyssop. Courtney Celley/USFWS, Public Domain. Get it at the source

Anise Hyssop: Several violet flower spikes on tall stems among shrubs — Agastache foeniculum. Asher P Higgins, CC BY 4.0, resized. Get it at the source

Anise Hyssop: Flower spike held in a hand, with a broken whorl at its base — Agastache foeniculum. Asher P Higgins, CC BY 4.0, resized. Get it at the source

Anise Hyssop: Opposite, toothed, egg-shaped leaves on a reddish stem — Agastache foeniculum. Asher P Higgins, CC BY 4.0, resized. Get it at the source

Anise Hyssop: Violet flower spike in front of Wild Bergamot's round pink-lavender heads — Agastache foeniculum. Brian Dickerson, CC0 1.0. Get it at the source

Anise Hyssop: Dark brown seed spike on a reddish stem — Agastache foeniculum. Jo Roberts, CC BY 4.0, resized. Get it at the source

Quick facts
Family	Lamiaceae · Mint
Status	Native perennial
Blooms	July and August, with a few in June and early September
Height	60–100 cm (2–3 ft)
Where	Moist gulches, stream banks, canyon bottoms, aspen and birch woods, and openings in pine forest
Also called	Blue Giant Hyssop, Lavender Hyssop, Giant Hyssop, Fragrant Giant Hyssop, Wild Anise, waȟpé yatȟápi (Lakota)
Synonym	Agastache anethiodora, Hyssopus anethiodorus, Hyssopus anisatus, Lophanthus anisatus, Stachys foeniculum, Vleckia anethiodora
Traditional use	Sitting Bull College's 1998 Culturally Important Plants of the Lakota says the Lakota made a tea from the leaves, chewed them for their licorice taste and to freshen the breath, and drank a leaf infusion for colds and fevers and to strengthen the heart.

Roots, seeds & germination

Root: A short taproot, with rhizomes that slowly spread one plant into a small clump over a few years. It doesn't spread aggressively like garden mint. The plant is short-lived but replaces itself by reseeding.

Seed: Each flower makes four tiny, smooth, oval brown nutlets, about 1.3–1.5 million to the pound. The seed ripens in late summer and fall, and the dark brown spikes stand into winter. Goldfinches eat the seed.

Germination: The seed sprouts easily and needs light, so it is pressed onto the surface or covered very thinly. At about 20 °C (68 °F) it comes up in one to four weeks. Cold, moist stratification isn't required but can help, and plants grown from seed can bloom their first year.

How do you identify Anise Hyssop?

Look for a square stem with opposite, coarsely toothed, egg-shaped leaves that are whitish underneath and smell strongly of licorice or anise when crushed. The small blue-violet to lavender flowers crowd into a dense, cylinder-shaped spike 3–10 cm (1–4 in) long at the stem tip, with four stamens poking out of each flower, and the base of the spike is often broken into separate whorls. Wild Bergamot, which often grows alongside, has one round, ragged pom-pom head, leaves green underneath and an oregano smell. Catnip is gray and downy, with whitish, purple-spotted flowers. The spikes turn brown and stand through winter.

When does it bloom?

July and August, with a few in June and early September.

Where does it grow?

Moist places: gulches, stream banks and floodplains, canyon bottoms, aspen and paper birch woods, hazelnut thickets, and openings or edges in ponderosa pine forest, at about 1,220–1,965 m (4,000–6,450 ft). The 1986 Jewel Cave survey lists it as Giant Hyssop, and National Park Service lists record it at Wind Cave and Mount Rushmore. More than 100 herbarium specimens come from the Black Hills counties, and it is photographed in Custer State Park.