Download The Alpha Plant - Bloomers Garden Center

June 30, 2013
Dr. Robert Nyvall
([email protected]
The Alpha Plant
There once was a Dormouse who lived in a bed
Of delphiniums (blue) and geraniums (red),
And all the day long he’d had a wonderful view
Of geraniums (red) and delphiniums (blue).
Nancy Hamlett, Biology professor, Claremont College
In my garden are what I call the “Alpha plant(s)”. Big hardy, blue-flowered, delphiniums.
One plant, in particular, towers above its neighbors, flaunting it’s dark green foliage and bursting
through its supporting cage. Hummingbirds and butterflies are frequently attracted to it’s blue
flowers. The fictional dormouse, referenced by Dr. Hamlett, would have a wonderful bed;
providing he didn’t eat the flowers.
Delphinium is a genus of about 300 species that are native throughout the Northern
Hemisphere and the high mountains of tropical Africa. The flower is surrounded by mystery,
myth and confusion.
The common name “larkspur” is shared between the perennial Delphinium species and annual
species of the genus Consolida ambigua. Two entirely different plant species. The name
Delphinium is derived from the Latin for dolphin and refers to the shape of the nectary, the
nectar-producing organ of a flowering plant. The common name larkspur comes from the shape
of the flower which resembles a lark’s spur or claw. True larkspurs have daintier flower spikes
with fewer florets and finer leaves than Delphiniums. A little imagination is required to grasp
both connections.
Delphiniums are elegant, stately perennials grown for their showy spikes of colorful summer
flowers in gorgeous shades of blue, pink, white, and purple. They are popular in cottage style
gardens and cutting gardens. The blooming plant is also used in displays and specialist
competitions at flower and garden shows, such as the Chelsea Flower Show. After blooming
flowers can be dried in a cool, dry place.
Most Delphinium hybrids and cultivars were developed, beginning in the 19th century, by a
Frenchman, Victor Lemoine, and were derived from one species, Delphinium elatum, a plant
native to the Alps. Subsequently, other hybrids have come from plants native to the Himalayas,
Siberia, Armenia, and California.
Today Delphiniums are classified by different groups and the differences can be confusing
and minute. The Belladona types have branched spikes lined loosely with individual flowers that
grow 3 to 4 feet tall. The Delphinium elatum hybrids have the showiest and tallest flower spikes
and grow 5 to 6 feet tall with the exception of the dwarf types. The “Alpha” plant in my garden
will grow up to 7 feet! These are considered basically the same as the Pacific Giant Hybrids
which are generally a couple of feet shorter. These are the plants you’ll find at Bloomers Garden
Center that come in blue, purple, pink and white with names like Aurora Blue Larkspur. Blue
bird larkspur, Pagan Purples Larkspur, Sweetheart Larkspur (a gorgeous rose to light pink color)
and Summer Morning Delphinium (a white, short flower for the smaller places in the garden).
All of these flowers are reported to grow 3 or 4 feet (with the exception of Summer Morning).
They are also reported to “tolerate” deer, a good attribute for our growing area.
However, the stems of these magnificent plants are hollow so it is strongly recommended that
a supporting cage or basket be placed around them or they be “staked” as they are susceptible to
breaking or bending during strong winds and rains. The exception are the dwarf perennials.
Plants bloom in late spring to early summer and the flowers are suitable for cutting.
Two other groups are the Millenium hybrids from New Zealand reported to do better in
warmer climates than Pacific hybrids and Delphinium cardinal, a California species that has been
hybridized to produce colors of red, orange, and pink.
A statement is repeated in much of the literature that Delphiniums are a “challenge” to grow
and is like teenagers, requiring constant feeding. Some references even state they are very
finicky and are considered short-lived perennials, declining after the 3rd season of growth! I
have not found this to be the case in my garden. Again, my “Alpha” plant is over 10 years and is
one of the first plants to appear in the spring, growing from a large, healthy crown. However,
plants do prefer moist, cool summers and do not fare well in hot, dry summers.
The factors in successfully growing Delphiniums are obvious and plant failure seems to be a
combination of the wrong soil type and light conditions. Generally, Delphiniums thrive in
relatively cool and moist summers but struggle in hot, dry weather. Ideally, Delphiniums should
be planted in the spring in a well-drained soil in full sun to light shade and sheltered from strong
winds. However, Delphiniums can be planted later in the summer if purchased as a strong potted
plant from Bloomer’s. The hole should be twice the diameter of the plant’s container and the top
of the root ball should be level with the soil line. Mix in 2 to 4 inches of compost in the planting
hole. Be sure to water thoroughly after planting. Delphiniums are alkalkine-loving (pH of 6.5
and above) plants that grow well together with phlox, allysum, and irises. Lime, wood ashes or
a combination of the two should be broadcast on the soil surface each spring. A mulch layer
around the plant base is also beneficial in holding down weeds and preserving moisture.
After planting insert supports or place cage around plants about the time plants are 12 inches
tall. Most importantly water plants throughout the summer if rainfall is less than 1 inch per
week. Some “experts” advise fertilizing every 2-3 weeks, others once a month and still others
once a year. My experience is to fertilizer once a year if plants are growing in a well-drained soil
high in organic matter. I apply a balanced fertilizer such as 5-5-5 or similar numbers after
flowering.
Some gardeners choose to dead head spent flower spikes back to small, flowering side shoots
and after blooming, cut flower stalks to the ground to promote development of secondary, but
smaller stalks. I don’t have the heart to do this and leave the plants alone as part of the vertical
texture in the garden.
Some gardeners advise dividing the crowns after 3 or 4 years. Again I have found this
unnecessary as the “Alpha” continues to thrive without division. However, this is a matter of
individual gardening taste.
That’s the good news, the bad news is Delphiniums and Larkspurs are poisonous. So a word
of caution to gardeners with small children; ingestion leads to nausea, vomiting, abdominal pain,
and muscular spasms. Death can occur. However, because there is nothing about the plant to
encourage ingestion, it is rated Category C by the Horticultural Trades Association as having the
lowest potential harm to humans. You would not use Delphinium leaves in your salad and there
has not been a reported case of poisoning to humans. Most poisonings are reported to be related
to cattle.
On the plus side, the plant has been used in herbal medicines and was used to treat intestinal
worms, fluid retention, poor appetite and insomnia. It was also used as a sedative to cause
relaxation, perhaps permanently. These uses are mostly reported from medieval times or people
with a death wish and are definitely not recommended for gardeners.
The bottom line is these gorgeous plants are meant to be looked at not eaten. And with a little
luck and care you too may be the proud observer of an “Alpha” plant that dominates the garden.