Also known as Giant Hyssop, Anise Hyssop, Blue Giant Hyssop, Fennel Hyssop, Fragrant Giant Hyssop. From the family Labiatae. Anise hyssop is a native of North America, the Mosquito Plant and A. mexicana 'Brittonastrum mexicana' are from Mexico, and A. rugosa is from Korea. There are few references to the history of this lovely herb. According to Allen Paterson, Director of the Royal Botanical Garden in Ontario, it is a close cousin of the Bergamots. It is common in North American herb gardens and is certainly worth including in any herb garden for its flowers and scent. The long spikes of purple, blue and pink flowers are big attractions for bees and butterflies.
Species
Agastache cana
The Mosquito Plant Hall-hardy perennial. Ht 60cm (2ft), spread 30cm (1ft). Pink tubular flowers in the summer with aromatic oval mid-green toothed leaves.
Agastache mexicana 'Brittonastrum mexicana' (or 'Cedronella mexican')
Half-hardy perennial. Ht 1m (3ft), spread 30cm (1ft). In summer whorls of small tubular flowers in shades from pink to crimson. Leaves oval pointed, toothed and mid-green with an eucalyptus scent.
Agastache rugosa
Korean Mint Hardy perennial. Ht lm (3ft), spread 30cm (1ft). Lovely mauve/purple flower spikes in summer. Distinctly minty scented mid-green oval pointed leaves.
Agastache foeniculum
Anise Hyssop Hardy perennial. Ht 60cm (2ft), spread 30cm (1ft). Long purple flower spikes in summer. Aniseed scented mid-green oval leaves.
Container Growing
Not suitable for growing indoors. However, anise hyssop and Korean mint both make good patio plants provided the container is at least 25- 30cm (10-12in) diameter. Use the bark, peat mix of compost, and a liquid fertilizer feed only once a year after flowering. If you feed the plant beforehand, the flowers will be poor. Keep well watered in summer.
Cultivation
Propagation
A. mexicana can only be propagated by cuttings.
Seed
The small fine seeds need warmth to germinate: 17°C (65°F). Use the cardboard method and artificial heating if sowing in early spring.
Use either prepared seed or plug trays or if you have only a few seeds directly into a pot and cover with Perlite. Germination takes 10-20 days.
One can also sow outside in the autumn when the soil is warm, but the voting plants will need protection throughout the winter months.
When the seedlings are large enough to handle prick out and pot on using a bark or peat mix of compost. In mid-spring, when air and soil temperature has risen, plant out al a distance of 45cm (18in).
Cuttings
Take cuttings of soft young shoots in spring: when all the species root well. Use 50pei cent bark, 50per cent peat mix of compost. After a full period of weaning cuttings should be strong enough to plant out in the early autumn.
Semi-ripe wood cuttings may be taken in late summer, use the same compost mix. After they have rooted, pot up, and winter in a cold frame or cold greenhouse.
Division
This is a good alternative way to maintain a short-lived perennial. In the second or third year divide the creeping roots either by the 'forks back-to-back' method, or by digging up the whole plant and dividing.
Pests and Diseases
Being an aromatic plant, pests keep their distance. Rarely suffers from disease, although seedlings can damp off.
Maintenance
Spring: Sow seeds. Summer: Take softwood or semi-ripe cuttings late season.
Autumn: Tidy up the plants by cutting back the old flower heads and woody growth. Sow seeds. Protect young plants from frost. Winter: Protect half-hardy species (and Anise hyssop below -6°C (20°F)) with either agricultural fleece, bark or straw.
Garden Cultivation
All species like a rich, moist soil and full sun, and will adapt very well to most ordinary soils if planted in a sunny situation. All are short lived and should be propagated each year to ensure continuity.
Anise hyssop, although hardier than the other species, still needs pro-lection below-6°C (20°F).
The Mexican half-hardy species need protection below -3°C (26°F).
Harvest
Flowers
Cut for drying just as they begin to open.
Leaves
Cut leaves just before late spring flowering
Seeds
Heads turn brown as the seed ripens. At the first sign of the seed falling, pick and hang upside down with a paper bag tied over the heads.
Other uses
Anise Hyssop, Korean Mini and Agastache mexicana all have scented leaves which makes them suitable for potpourris.
Culinary
Anise Hyssop
Leaves can be used in salads and to make refreshing tea. Like borage, they can be added to summer fruit cups. Equally they can be chopped and used as a seasoning in pork dishes or in savory rice.
Flowers can be added to fruit salads and cups giving a lovely splash of color.
Korean Mint
Leaves have a strong peppermint flavor and make a very refreshing tea, said to be good first thing in the morning after a night on the town. They are also good chopped up in salads, and the flowers look very attractive scattered over a pasta salad.