Agastache is a genus of herbaceous perennial plants in the Lamiaceae (mint family). The common names for this plant include giant hyssop, hummingbird mint, licorice mint, and anise hyssop. There are multiple other common names used for the different species in this genus.
The genus Agastache includes about 22 species that are native to North America and parts of Mexico. These aromatic herbs are prized by gardeners for their spikes of tubular flowers that attract pollinators like bees, butterflies, and hummingbirds. The flowers come in shades of blue, purple, pink, orange, and yellow depending on the species. When the leaves are crushed, they emit a licorice or anise scent. Agastache plants are easy to grow, tolerate heat and drought, and have few pests or problems. They make great additions to herb gardens, perennial borders, wildflower meadows, and pollinator gardens. The flowers, leaves, and seeds of Agastache plants have been used traditionally by Native Americans for medicinal purposes and can also be used for culinary purposes.
Other Common Names for Agastache
Here are some of the other common names used for the different Agastache species:
Giant Hyssop
This common name refers to several of the larger growing Agastache species such as:
- Agastache foeniculum (anise hyssop or blue giant hyssop)
- Agastache rugosa (Korean mint or wrinkled giant hyssop)
- Agastache scrophulariifolia (purple giant hyssop)
The name “giant hyssop” refers to the fact that some Agastache can grow over 6 feet tall, much larger than traditional garden hyssop (Hyssopus officinalis).
Hummingbird Mint
Many of the tubular flowers of Agastache attract hummingbirds, leading to common names like:
- Agastache aurantiaca (orange hummingbird mint)
- Agastache cana (mosquito plant or Texas hummingbird mint)
- Agastache pallidiflora (New Mexico hummingbird mint)
Licorice Mint
The anise/licorice scent of the foliage accounts for common names such as:
- Agastache foeniculum (anise hyssop or licorice mint)
- Agastache mexicana (Mexican giant hyssop or Mexican licorice mint)
- Agastache nepetoides (yellow giant hyssop or licorice mint)
Anise Hyssop
Agastache foeniculum is most commonly known as anise hyssop. This name refers to the anise-like fragrance of the leaves.
Key Species and Cultivars
Here are some of the most popular Agastache species and cultivars used in gardens:
| Species/Cultivar | Description |
|---|---|
| Agastache foeniculum | Anise hyssop or blue giant hyssop with blue to purple flowers and licorice scented foliage |
| Agastache rugosa | Korean/wrinkled giant hyssop with lavender-blue flowers |
| Agastache aurantiaca | Orange hummingbird mint |
| Agastache x ‘Black Adder’ | Dark purple flowers on compact 18-inch plants |
| Agastache x ‘Blue Fortune’ | Long blooming hybird with smoky purple and blue flowers |
| Agastache x ‘Kudos Coral’ | Coral-pink flowers on compact plants |
| Agastache x ‘Kudos Gold’ | Golden yellow foliage with orange blooms |
| Agastache x ‘Tutti Frutti’ | Multicolored flowers in shades of pink, orange, yellow |
Growing Conditions
Agastache thrive in full sun and well-drained soil. They prefer drier conditions and are drought tolerant once established. Here are some tips for growing Agastache plants successfully:
- Plant in spring after the last frost
- Space plants 18-24 inches apart in the garden
- Grow in loose, sandy or gravelly soil for best drainage
- Let soil dry out between waterings
- Pinch back tips to encourage bushy growth
- Fertilize lightly with a balanced fertilizer in spring
- Cut plants back to 6 inches after flowering finishes
- Mulch over winter in cold climates
- Divided large clumps every 2-3 years to promote vigor
- Propagate by cuttings or division in spring or fall
With their preference for dry conditions, Agastache are excellent plants for xeriscapes and rock gardens.
Pests and Diseases
Agastache are typically not bothered by many pests or diseases, especially when grown in dry, well-draining soil. Possible problems to watch for include:
- Aphids – These small sucking insects can cluster on new growth but are easy to control with horticultural oil or insecticidal soap sprays.
- Spider mites – These tiny mites may appear during hot, dry weather. Knock them off with a strong spray of water.
- Powdery mildew – This fungal disease causes a white powdery coating on leaves during wet conditions. Improve air circulation to prevent it.
- Root rot – Overwatering can lead to fungal root rot. Allow soil to dry between waterings.
By choosing disease resistant varieties, proper siting, and smart watering practices, serious Agastache plant problems can be avoided.
Uses in the Garden
With their spikes of tubular flowers, Agastache add beautiful colors and textures to gardens. They have many uses such as:
- Mass plantings or specimen plants in perennial borders
- Container plantings on patios or porches
- Edging plants along walks or walls
- Groundcovers for blank spaces between taller plants
- Accent plants in rock gardens, walls, or xeriscapes
- Cut flowers for bouquets
- Dried flowers for everlasting arrangements
The vertical flower spikes contrast nicely with bushy, mounding foliage plants. Try combining Agastache with Russian sage, catmint, salvia, daylilies or ornamental grasses. Agastache also attract birds, bees and butterflies to any garden.
Culinary and Medicinal Uses
Certain species of Agastache have uses beyond the ornamental garden. For example:
- Leaves and flowers can be used to make herbal teas.
- Flowers can provide flavoring for jellies, desserts and beverages.
- Leaves add fragrance when potpourri or sachets.
- Essential oil extracted from leaves has licorice scent notes.
- Used in traditional Native American medicine to treat coughs, fevers and digestion.
Anise hyssop (Agastache foeniculum) is the most culinary species. It has sweet, anise-flavored leaves that can be used fresh or dried for teas, desserts, potpourri and more. Do some research before consuming Agastache plants from the landscape as not all species are edible.
Propagating Agastache Plants
Agastache can be easily propagated in spring or fall by:
Cuttings
Take 4-6 inch cuttings from healthy stems. Remove lower leaves and place cuttings in potting mix. Keep soil moist under gentle light until roots form.
Division
Mature Agastache clumps can be divided in spring. Carefully dig up plant and separate sections with a shovel or knife. Replant divisions and keep watered until established.
Seed
Start Agastache seed indoors 8-10 weeks before last frost. Barely cover seeds with soil, keep moist, and grow seedlings under lights. Harden off before transplanting outside.
Conclusion
Agastache is a versatile genus of flowering perennials that deserves a place in any garden it can grow. With needle-like flowers in shades of purple, blue, pink, orange, yellow and beyond, it provides color and interest from midsummer into fall. The licorice-scented foliage is a bonus. Give Agastache plants full sun, well-drained soil, and moderate water for best performance. Use it to attract hummingbirds and butterflies or as beautiful cut flowers. With very few pests or problems, Agastache is an easy care, high impact perennial.
