Agastache rugosa                                   Family: Lamiaceae
(ag-ak-STAK-ee roo-GO-sah)
syn. Lophanthus rugosus

Common name: Korean mint; purple giant hyssop
Zone: 5 – 9
Height: 24 – 36 in (60 – 90 cm)
Spread: 24 in (60 cm)
Aspect: full sun; partial shade
Soil: moist; well-draining
Water: regular


Description:
An herbaceous perennial with an erect habit. Oval, closely-toothed, medium green leaves are slightly hairy on their underside. Short spikes of lavender-blue flowers appear from mid-summer through to early fall. Small seeds are black.


Special Notes:
Native to Korea, Japan, China and Vietnam. Leaves have a strong mint and liquorice scent when rubbed. Ornamental and medicinal plant used for teas, seasoning meats and in Eastern medicine. Perfect dried flower. Attracts bees and butterflies. Relatively few pests and disease problems but watch for powdery mildew. Propagate by seed, by cuttings in early spring or in summer, or by division in early spring or autumn.


In our Zone 7a garden:
I have placed a few of these plants in my front bed where they must compete with the roots of my mature Aesculus hippocastanum (European horse chestnut) and Acer saccharinum (silver maple) trees. The soil is not stellar in this area of my garden and I have a hard time getting enough water to the plants. The two trees are famous for sucking all of the benefits out of the soil. Having said that, Agastache rugosa is one plant species that survives in my garden under these tough conditions, despite what the reference sources stipulate are its growing needs. Of course, it is not as lush as if it were provided fertile soil and adequate water but by planting more plants close together I can achieve roughly the same effect as from one plant alone.

 

Posted on March 13, 2013; updated on August 5, 2024