Anise Hyssop

Growing Conditions

Growing Zones

Thrives in USDA Zones 4 - 9

Companion Planting

When to Plant

• Start Indoors

  8-10 weeks before last frost

• Transplant

  After last frost, when nights are reliably above 40°F

• Direct Sow

  Direct sow in early spring when soil reaches 60°F, or sow on surface in fall for spring germination

• Harvest

  Harvest leaves anytime once plants are established and leafy; cut flower spikes as blooms open for fresh use or drying; deadhead spent spikes to extend the bloom season and encourage reblooming

Organic Growing Tips

• Top-dress established crowns with a thin layer of finished compost each spring to encourage vigorous new growth without promoting the lush, disease-prone growth that excess nitrogen causes

• A light mulch of straw or shredded leaves around the crown moderates soil moisture and suppresses weeds without smothering the plant; pull mulch back from the crown itself to prevent rot

• Worm castings worked into the planting hole at transplant time improve soil biology and gentle nutrient availability without burning young roots

• Compost tea applied as a soil drench in early spring activates beneficial soil microbes and supports the shallow, fibrous root network that anise hyssop relies on

• Allow a few flower spikes to go to seed each season to encourage self-sown volunteers; transplant or thin these in early spring before they crowd established plants

• Divide overcrowded clumps every 3-4 years in early spring using a sharp spade; replant divisions immediately and water in well to maintain vigor and prevent crown rot in the center

Common Pests

• aphids
• Japanese beetle
• spider mites
• powdery mildew

Taxonomy

Kingdom

Plantae

Family

Mint family (Lamiaceae)

Genus

Agastache

Species

foeniculum

Natural History

Agastache foeniculum is native to the north-central prairies and open woodlands of North America, ranging from the Great Plains into the upper Midwest and Great Lakes region. Indigenous peoples of the Great Plains and Great Lakes, including Chippewa and Cree communities, cultivated and gathered the plant long before European contact. The genus name Agastache derives from Greek meaning 'many spikes,' referencing the plant's dense flower whorls, while foeniculum reflects its fennel-like fragrance. European settlers adopted anise hyssop as a tea herb and garden ornamental in the 18th and 19th centuries. As a short-lived perennial, it maintains populations in the garden through prolific self-seeding, a practical trait growers can either channel or manage through deadheading.

Traditional Use

Several Indigenous nations of the Great Plains and Great Lakes documented historical uses of Agastache foeniculum leaves in traditional practice. The plant's aromatic properties were noted in ethnobotanical records of the late 19th and early 20th centuries, particularly among Chippewa communities documented by ethnobotanist Frances Densmore. Its role was primarily aromatic and ceremonial rather than pharmaceutical in most recorded traditions.

• Chippewa (Ojibwe), Great Lakes region, recorded by Frances Densmore ca. 1910s - leaves

  Densmore's ethnobotanical records noted that Chippewa people used the fragrant leaves in the context of ceremonial and aromatic practice; the plant was gathered from native prairie stands and valued for its distinctive anise scent

• Cree, northern Great Plains and boreal fringe, 19th–20th century - leaves

  Cree ethnobotanical records document the leaves as an aromatic plant gathered for flavoring and fragrance purposes, with the plant sometimes incorporated into preparations described in historical notes as similar to tea in form

Anise hyssop is widely regarded as safe for culinary use at food quantities; individuals with known allergies to Lamiaceae family plants should exercise caution, and the plant's essential oils are concentrated enough that very large quantities may cause sensitivity in susceptible individuals

This information is provided for historical and educational purposes only and is not medical advice. Always consult a qualified healthcare professional before making decisions related to your health.

Morphology (Plant Structure & Identification)

• Root System

  Fibrous, shallow crown-forming root system that spreads slowly over time; crowns can be divided every few years in early spring and the plant self-sows freely, making it self-perpetuating in the garden without becoming aggressively spreading

• Stem

  Upright square stems typical of the mint family, reaching 2-4 feet tall, lightly branched in the upper half; stems are sturdy enough to stand without staking but benefit from light deadheading to encourage side branching and extended bloom

• Leaves

  Opposite, ovate leaves with serrated margins and a strong anise-licorice fragrance when crushed; leaves are medium green above and slightly paler beneath, and both young and mature leaves are equally flavorful for culinary harvest

• Flowers

  Dense, elongated spikes of small tubular lavender-blue to purple flowers arranged in whorls; blooms attract an exceptional diversity of bees, butterflies, and hummingbirds and can be harvested fresh or dried for tea and garnish when fully open

• Fruit

  Spent flower spikes produce abundant small nutlet seeds that drop and germinate readily; deadhead after bloom to prevent excessive self-sowing, or allow some spikes to mature and scatter seed to naturalize the plant in a designated garden area

Known Varieties

Common cultivars worth knowing

• Blue Fortune

  A sterile hybrid (Agastache foeniculum × A. rugosa) with large, long-lasting blue-purple flower spikes and reduced self-seeding; more uniform in habit than straight species and particularly vigorous in mid-summer heat

  Best for: Ornamental beds, pollinator gardens, growers who want bloom without volunteer seedling management

• Golden Jubilee

  A cultivar selected for bright chartreuse-gold foliage that contrasts dramatically with the lavender-blue flowers; equally fragrant and edible, and a strong performer as an ornamental herb

  Best for: Ornamental kitchen gardens and containers where foliage color is valued

• Liquorice Blue

  A tall, straight-species-type selection with particularly rich blue-purple flower spikes and strong anise fragrance; reliable bloomer in its first year from an early indoor start

  Best for: Culinary herb gardens and cut flower use

• Agastache foeniculum (straight species)

  The native straight species; freely self-sows, forming naturalized colonies over time with true-to-type fragrance and excellent pollinator value; shorter-lived as an individual plant than named cultivars but maintains itself through seeding

  Best for: Native plant gardens, prairie-style plantings, and growers who want a self-sustaining population