Agastache is a genus of about 30 aromatic species native to central and eastern Asia, Mexico, and the United States: A. foeniculum is native to the United States; A. rugosa is from China and Japan. Careful breeding and selection have given us newcomers that offer exceptional garden performance and a long season of bloom. In full sun and well-drained soil, they happily shrug off summer heat and early frosts.
Light/Watering: Full sun. Some afternoon shade will protect the leaf color of yellow-foliaged Agastaches.
Fertilizer/Soil and pH: Average garden soil that drains well. Do not fertilize the first spring after planting; in subsequent years fertilize once in early spring with 10-10-10 or a layer of well-rotted compost. Acid to neutral pH.
Pests/Diseases: Few insect problems. Mildew can affect the leaves during dry summer weather. Deer generally do not bother Agastache, which is a member of the Mint family.
Companions: Other plants that prefer full sun and well-drained soil make good partners, for example: Milkweed (Asclepias), grasses (especially shorter varieties of Festuca), Yarrow (Achillea), Gaillardia, or Russian Sage (Perovskia). The bushier varieties of Agastache hold their own against most other perennials in a sunny border.
Dividing/Transplanting: Divide in spring if plant has outgrown its space; plant crown at soil level.
Calendar of Care - Agastache
Early Spring: Gradually remove any winter cover. Cut back old stems; large clumps may be divided. Apply one application of balanced 10-10-10 fertilizer or a 1–2″ layer of well-rotted compost (keep at least several inches away from the plant's crown).
End-of-Season Care: Cut stems back half way to protect the plants from damage by winter winds.