AR Gardener Magazine
Articles
Amsonia hubrichtii, Arkansas Blue Star
Native plants are the rage in gardening, but frankly, few of
them will every become commonplace in the perennial border. One that deserves
this kind of attention is Amsonia hubrichtii. It possesses the toughness
of the best native plus the grace and charm of a well refined perennial
providing a long season of interest in the garden.
The most common Amsonia in gardens and in Arkansas is A.
tabernaemontana which occurs in the eastern woodlands south a line from
Missouri to Virginia. Unlike the wide range of the common blue star, A.
hubrichtii is found almost exclusively in the Ouachita mountains of Arkansas
and Oklahoma. The species was only recognized as distinct in 1943 when a
botanist from the Missouri Botanic Garden grew material provided by Leslie
Hubricht, an expert on fresh water mollusks. Hubricht had been on a collecting
trip for the Field Museum of Natural History in Chicago the year before when he
ran across the unusual Amsonia in Garland County. When the botanist, Robert
Woodson, investigated he found that the plant had been collected periodically
since 1879 but had been consistently misidentified as A. ciliata var.
filifolia.
Arkansas blue star grows to three feet tall with the stems
arising from a crown. The graceful branches arch outward from the crown and
spread to four feet wide on mature plants. The leaves are linear to three inches
long and almost grass-like in appearance. In the summer these lacy plants
provide an interesting textural contrast for most other plants you are likely to
be growing in your garden. In the fall, the foliage turns a golden yellow and
persists for about three weeks. Fall is its most beautiful period in the garden.
Flowers appear in late April and May once the stems have
attained their maximum length. The flowers are often described as "sky blue" but
that would have to be on a very hazy day for they tend towards light blue to
almost white. They are borne terminally in panicle and hide amongst the foliage
at the top of the plant. Individual flowers have the typical, 5-pointed star
associated with the Amsonia and are about 3/4 of an inch across. The seed pod is
an elongated, cigar shaped follicle that is about the size of a large toothpick.
The Amsonia belong to the dogbane family along with Vinca
minor and the common periwinkle (Catharanthus roseus), and like many
members of that family, have a milky sap. The sap of some species in the family
contain toxic alkaloids which have been used medicinally and can be toxic to
livestock. For the gardener this is good, because Amsonia are often listed as
"deer-proof" plants.
The Arkansas blue star is easiest to propagate from summer
cuttings, ideally collected from a non-flowering stem. Four inch long cuttings
root in about three weeks under mist and will be large enough to transplant to
the garden the following spring. Seed is available, but germination tends to be
somewhat erratic. It should be kept uniformly moist and stratified at 45 degrees
Fahrenheit for at least two weeks. After this, seeds should be kept in a moist,
cool (below 60 degrees Fahrenheit) location until germination is complete, which
can take up to two months. Many native plant nurseries carry the plant as does
Wayside Gardens.
Like most Amsonia this species is adapted to any well drained site in either
full sun or partial shade. It does best with a slightly acidic pH and is not
generally considered finicky about soil conditions. The first year after
planting, Amsonia hubrichtii will look a bit spindly and unpromising.
Allow the clump a couple years to fully expand and its beauty will be a thing to
behold, especially in the fall.
This story first appeared in the
AR
Gardener Magazine.
By: Gerald Klingaman, retired
Extension Horticulturist - Ornamentals
Plant Profile - July-August 2001
Back to AR Gardener Magazine Articles
|
