Calochortus--TOW--High Elevation Species

diana chapman
Wed, 10 Nov 2004 08:27:25 PST
 From 2000:

In this discussion, I will try to cover some of the high-altitude species
that can be somewhat more challenging to grow.  These species absolutely
require a cold winter, and their smaller stature can make some a very
desirable addition to the rock garden in suitable climates.  Although they
are generally tolerant of summer water, exposed as they are to the summer
storms of the mountains, like all Calochortus they require excellent
drainage, with the desert species requiring very dry growing conditions.
  Most species make superb alpine house subjects.  The alpine species of
Calochortus are dormant in winter, making most of their growth in spring
after the snows melt, and blooming in early to late summer, when they then
scatter their seed and go dormant.

Some High Altitude Mariposas:

Calochortus gunnisonii ---  This beautiful Calochortus is found in the
Rocky Mountains, usually around 2-3000m, where it experiences extremely
severe winters, making it the hardiest Calochortus in the entire genus.
  Flowers are upward facing, white, pink or lavender, with the interior
lower one third covered with black based golden hairs.  There is often a
deep purple band separating the hairy part of the petal from the upper two

Calochortus leichtlinii  ---  Generally found around 1500-4000m all down
the backbone of the Sierra Nevada mountains, as well as the higher
altitudes of the mountain ranges of northern California and southern
Oregon.  This is a beautiful species, a dazzling white that is difficult to
describe with black or very dark crimson markings at the base of the
petals.  There are some yellow markings at the base of the petals, although
in the ones I grow, these are not very prominent.  It is quite common in
its range.

Calochortus bruneaunis  ---  This species occurs mainly in the mountain
ranges of the Great Basin, growing in very dry, cold conditions with very
high light intensity.  It is somewhat similar in appearance to C.
leichtlinii, with some golden markings in the center.

Calochortus excavatus  ---  This lovely species superficially resembles
both C. leichtlinii and C. bruneaunis, and comes from a very restricted
area on the eastern slopes of the Sierra Nevada in its southern end, around
Bishop and the Owens Valley.  This, too, comes from very harsh desert
conditions with cold winters.

Calochortus panamintensis  ---  As the name suggests, this species is from
the Panamint mountains of southern California growing in very dry, cold,
desert conditions very similar to the habitat of C. bruneaunis at
elevations of 2500-3500m.  The flower is white tinted lilac, with a very
prominent green stripe to the outside of the petal, and often a deep purple
spot around the nectary.

Calochortus nuttallii  ---  This may be the most widespread Calochortus of
all, occurring as it does from Nevada northeast into the Dakotas, and
southeast into New Mexico, occurring generally in high desert conditions.
  In the southern part of its range, however, conditions are somewhat milder
than in the northern region, therefore different populations may require
different growing conditions.   Flowers are white to deep pink with
brownish markings above the nectary, and lacking an exterior green stripe
on the petal.  This species is commonly called Sego lily, derived from its
Shoshone name.

Calochortus macrocarpus  ---  Found in central Washington, across Idaho
into the northern part of the Great Basin,  and extending northward up to
British Columbia, this species also covers and extremely extensive range.
  In the high desert regions at elevations of over 1500m where this species
grows it endures very cold winters throughout most of its range, in
addition to extremely hot summers. Flowers are large, light to deep purple,
with a prominent green stripe to the outside of the petal.  There is
usually a deep purple band above the nectary.

High Altitude Star Tulips:

Calochortus minimus  ---  As the name suggests, this is the smallest
Calochortus, growing only about 10cm tall, and comes from the high
elevations of the central Sierra Nevada. While not showy, with its plain
white petals, it does have a certain charm, and is reputed to be one of the
easier high altitude Calochortus to grow.

Calochortus nudus  ---  Somewhat similar in appearance to C. minimus, this
species grows in the northern range of the Sierra Nevada. The range of both
of these species overlaps, and hybrids can be found in the overlapping
region.  C. nudus has pink to lavender flowers, also unmarked, but the
flowers are larger.

High Altitude Cat's Ears:

Calochortus subalpinus  ---  This species is found in mountain meadow
habitats in the Cascade mountains of Oregon and Washington, where, unlike
the high altitude Mariposas, it occupies a range that receives very heavy
rainfall which occurs mostly in winter, but it is also exposed to summer
rains.  The flowers are upward facing, the petals completely covered with
silky hairs, and the color range is cream, pale yellow or buff.

Calochortus tolmiei  ---  This species can occur at sea level, but is most
commonly found at higher elevations of up to 2000m, in the Coast Range of
California, as well as the Sierra Nevada, and the northern California
ranges into Oregon and Washington.  This is a small species, with a very
neat growth habit, usually of about 25-20cm.  Flowers come in a range of
white, lavender, pink and violet, often with deep purple central markings,
and the petals are densely hairy.  This beautiful Calochortus is quite easy
to grow.

Calochortus coeruleus  --- Found in the northern Sierra Nevada and the
northern Coast Ranges, but more commonly found at high altitude in Oregon
and Washington, this species superficially resembles C. tolmiei but is
white tinted blue.

Growing the High Altitude Species:

These species have always had a reputation for difficulty, but this may be
because many Calochortus lovers (such as ourselves) are growing them in
mild-winter regions, where both seed and bulbs do not receive adequate
winter chilling.  In addition, many of the alpine species require rather
cool summers to successfully complete their growth cycle.  Obviously,
no-one will be able to grow all of the species mentioned, but some are
really worth trying, especially for those IBS members who live where
winters are severe.


Seed of many species can be had from Northwest Native Seed (Ron Ratko),
Southwestern Native Seed, or the Archibalds.  Seed of all the species
mentioned must be sown in the fall, and stratified in the refrigerator for
those who live in warmer climates than USDA zone 6. The exception to this
is C. tolmiei, which can be sown in fall and exposed to winter weather in
zones 7 and 8.  I usually place the seed in very slightly damp peat or
vermiculite in a zip-lock plastic bag, and place it in the food compartment
of the refrigerator in about October (northern hemisphere).  The seed
absolutely should NOT be frozen, even when you are germinating seed from a
species such as C. gunnisonii that would be in frozen or close to frozen
ground for months. Once the seed has imbibed moisture, freezing can be
fatal.  Seed bags should be checked about once a week after the first
month, and any germinated seed should be potted up.  All species should be
left in the refrigerator UNTIL THEY GERMINATE - i.e. until you see the
emergence of a radicle.  Some species will require three or four months at
refrigerator temperatures, but some will germinate sooner.    The alpine
desert species from southern California need to be potted in a very free
draining mix containing very coarse grit or perlite (or both), and a little
lime, since the soils they grow in desert regions are on  the alkaline
side.  Other Calochortus species do not seem fussy about pH.  Seedlings
should be kept in a covered area to protect from excessive rain, but
exposed to winter temperatures.  Obviously, if you live in a region with
cold winters (USDA zone 6 or colder), you will be able to sow your seed in
the fall and leave your seed pots outside exposed to the weather, but
protected from birds and rodents.  Most of the alpine species have a much
shorter growing period than the low elevation species, and therefore the
bulbs will take longer to mature.


If your winters are mild, it will be necessary to refrigerate your bulbs
each winter.  This can be done by removing the bulbs from your pots, and
putting them in dry peat in the food compartment of your refrigerator each
winter, starting in about October.  It is necessary to check the bulbs
every two weeks or so for root growth, for if they start energetically
producing roots, you will need to take them out and pot them up.  Some
species need extended refrigeration (up to four months), while others need
only six to eight weeks. The ideal refrigerator temperature for the
chilling of Calochortus is one or two degrees above freezing.

I have to admit that I haven't been growing some of the above species long
enough for them to bloom, but most seem to be doing well so far.  Bringing
a more difficult or rare species to flower is a special joy in itself, and
many of these species should prove easier for those member who live in
colder climes than California.


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