Garden Mastery Tips
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Summer 2009 |
Cobra Lillies…Exotic and Intriguing
The Cobra lilly, or Arisaema (pronounced air-uh-SEE-muh) is a genus of the Arum family and found mostly in Asia and North America. They are a plant collector’s latest craze, definitely fascinating, and sort of mysterious and strange. You won’t find them at garden centers or even at many specialty nurseries. Even though many gardeners have never heard of them, they are exotic, and are relatively easy to grow. A favorite of collectors is the variety A. candidissimum from western China. Its flowers look like porcelain: translucent white with rose streaks. Another one highly prized is A. sikokianum, known as the Japanese cobra lilly. This splendidly arrogant specimen sports a soaring spadix that’s pure white, with a large “knob” and a purplish spathe.
Another common name for this mysterious plant is “Jack in the Pulpit”. The “flowers” (inflorescences) consist of a “club” shaped or whip-like appendage (the spadix) inside a hooded tube (the spathe). Hence, they are, respectively, the “Jack” and the “pulpit”. One important attribute to keep in mind is that they are also listed as a poisonous species.
You can refer to them as beautiful or bizarre, but they are definitely fascinating and they will always elicit comment in your garden. Most gardeners treat preacher Jack as a novelty. Now you can call them “Jack” OR “Jill” because they have a strange ability to change their sex. Some plants are male, some are female, some are both, and some change back and forth. As a general rule, Arisaemas are male when young, then when they build up enough energy to have babies, they switch and become female. The year after they give birth (or fruit), they will often revert back to being male. AND, there are a few that always have both sexes on the same plant.
These unique plants require shade and good drainage. They are tuberous, come in a variety of heights and make a great “pop-up” addition when mingled with hostas and ferns, or are spectacular when planted en masse. Bloom time depends on the variety and ranges from early spring through summer. Arisaemas are quite hungry plants. Water sparingly until new growth emerges in the spring, and then it is recommended that you feed the plant every two weeks (a light solution of Miracle Grow is suggested). After the plant flowers and the leaves begin to wither, stop feeding. At this point, the plant is beginning to enter dormancy. All varieties produce showy red or orange fruit heads in late summer to fall.
Most Arisaemas are frost hardy down to -10 degrees Fahrenheit. The more tender varieties of tuber can either be dug up and stored in slightly damp peat in a freezer bag and left in the refrigerator at 35–40 degrees, or left in the ground with a generous layer of mulch. They require some winter moisture, but will rot in heavy soil and too much water. Some reproduce through offsets (or babies) which can be separated from the mother tuber to increase stock. Others can be propagated only from seed. To get seed of most species, you will need both a male and female plant. Tissue culture has been attempted on Arisaema, however, their complex dormancy patterns and difficulty of sterilization thus far has rendered this process impossible.
Resources
Gardening Life, 22 March 1999, Author: Sonia Day
“Desire Under the Jacks” by Ken Druse
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