from July 2000
The typical California gardener would consider salvias an essential part of a proper landscape and would be at least passingly familiar with the ornamental thymes, nepetas and oreganos. Yet a decade or two ago, most of these plants were barely known outside the herb garden. Now it is time to look more deeply into the vast mint family (Lamiaceae) for less familiar treasures. The agastaches, stars of this month's column, hold a special place in my heart.
Agastache is primarily an American group, especially prominent in the Southwest and Mexico. Its members are herbaceous perennials which form compact colonies from underground stems. Crowns of low-lying basal leaves appear in spring (sometimes they are evergreen), gathering forces for a while. Then many slender, leafy, usually well-branched stems rise above them, creating an airy mass. The stems are conspicuously 4-sided and ridged like those of many salvias. The leaves may be broad or narrow, toothed or smooth-margined, and deep green to a striking chalky grey in color. Both leaves and stems are aromatic, often delightfully so. Crowded flower clusters are produced at each shoot tip. These may remain short and dense or gradually extend into long torches as the flowers open. The individual flowers are narrow tubes with irregularly parted "faces", painted white to violet, magenta to yellow. Backlit by the sun, they seem to glow from within. Often the calyx is also vividly colored. The flowers are not only stunning to human spectators. They are equally attractive to hummingbirds and a host of butterflies. When the last flowers are spent, a repeat performance can often be coaxed by cutting the stems back hard.
With a few exceptions, agastaches are sun-loving, heat-tolerant plants. Most appreciate well-drained soils. Those which insist on it can be grown on banks or in raised beds or renewed annually by seeds or cuttings (they are easy for even the home gardener to propagate). Many are at least moderately drought tolerant, though the plants are more impressive with normal garden watering. The following are hardy outdoors in coastal California, and some are at home in much colder climes.
First, the species. A. cana is one of my personal favorites, and one of our most recent acquisitions. It is a southwestern native growing 1-2' high, of delicate, lacy appearance. The stems are grey-hairy, the leaves light green and narrow. Details of the flowers and flower clusters are often quite variable. We are fortunate to have received material with exceptionally large purplish rose flowers borne in generous clusters. This is a plant most at home on sunny banks. A quite different plant is A. urticifolia 'Sierra Beauty', which I found in the high Sierra (it is also common in the lowlands). This is a bushy plant growing 2-3' high. The leaves are nearly triangular in outline, toothed, and deeply veined. The small flowers are borne in dense clusters, their white tubes and faces contrasting nicely with rosy lavender calyces. Grow this one in an ordinary garden setting. 'Blue Fortune' is a selected form of A. foeniculum, another undemanding perennial. It is a leafy plant growing 2' or more high. The leaves are large, toothed and dark green above, pale beneath, with a sweet, anise-like scent and taste. Interrupted spikes of violet-colored flowers are borne at the shoot tips throughout the warmer months.
We have Ginny Hunt to thank for several garden hybrids. 'Summer Breeze' is my all-time favorite, with 3-5' high, graceful stems, sweetly scented grey-green leaves and long, interrupted clusters of beautiful 1"+ flowers. These are tinted an unusual coral-pink in bud, purplish pink when expanded. 'Tangerine Dreams' is similar in scale, with broader, greener leaves and an intriguing pennyroyal scent. The flower clusters are more open, and the 1 ½" flowers combine a rosy calyx, orange tube and rosy lavender stamens and pistils. A third hybrid, identified only as "mexicana hybrid", is a robust plant with large toothed leaves and pink to magenta flowers up to 2" long. All are easily grown, though they may not persist in winter-saturated soils.
Try agastaches in your own garden. You'll be hooked forever.