Basic Information
Common Name: Arisaema
Scientific Name: Arisaema
Native Habitat: Primarily found in Asia (China, Japan, Himalayas) and eastern North America.
History / Discovery / Cultivator
Arisaema, commonly known as cobra lilies or jack-in-the-pulpits, has a history deeply intertwined with the flora of Asia and North America. The genus Arisaema was first formally described by Martius in 1831, although species within the genus were recognized even earlier under different classifications.
The discovery and categorization of individual Arisaema species are largely attributed to the meticulous work of botanists and plant explorers over several centuries. For example, numerous species native to China were identified and classified by Western botanists during the 19th and 20th centuries. Robert Fortune, a Scottish botanist, is notable for introducing many Asian plants to Europe in the mid-1800s, and while he may not have specifically focused on Arisaema to the exclusion of other genera, his explorations undoubtedly contributed to the understanding of Asian flora where Arisaema thrive.
In North America, the common Jack-in-the-pulpit (Arisaema triphyllum) has a long history of recognition. Indigenous peoples utilized various parts of the plant, with caution, for medicinal purposes, such as treating headaches and skin ailments. European settlers also recognized the plant’s presence and its potential uses, although its toxicity was quickly understood and respected.
Cultivation of Arisaema has grown in popularity among gardeners and plant enthusiasts, particularly those interested in unique and exotic plants. Certain species, such as Arisaema candidissimum with its pink-striped spathe, and Arisaema consanguineum with its numerous leaflets, are highly sought after for their striking appearance. The geographical origins of various Arisaema species are diverse, with significant concentrations in the Himalayas, China, and Japan. Different species have adapted to a wide range of habitats, from moist woodlands to rocky slopes. This diversity makes cultivation both challenging and rewarding, as different species have varying requirements for soil, light, and moisture. Dedicated Arisaema collectors often seek out rare and unusual species, contributing to the ongoing exploration and propagation of these fascinating plants. The Arisaema Research Group (ARG) founded by Guy Gusman and Tim Brotzman, now coordinated by Michael Hagen, serves as a valuable resource for enthusiasts.
Plant Care Summary
| Category | General Requirement | Notes |
|---|---|---|
| Light | Partial Shade | Avoid direct sunlight, especially during the hottest parts of the day. |
| Water | Moderate | Keep soil consistently moist during the growing season, reduce watering during dormancy. |
| Humidity | Moderate | Benefits from increased humidity, but generally adaptable. |
| Temp. Range | Cool to Moderate | Avoid extreme heat, especially during dormancy. |
| Soil Type | Well-draining | Requires humus-rich soil with good drainage to prevent rot. |
| Fertilizer | Light Feeding | Apply a balanced fertilizer sparingly during the growing season. |
| Toxicity | Highly Toxic | Contains calcium oxalate crystals; causes intense oral pain and irritation if ingested. |
Botanical Insights
Adaptations
Arisaema species exhibit several fascinating adaptations. One of the most notable is their unique pollination strategy. The “Jack-in-the-pulpit” structure (spadix and spathe) traps small insects, particularly flies, which are attracted by a scent mimicking fungi. Some insects are trapped temporarily and dusted with pollen before being released to pollinate other plants. Another adaptation is their ability to go dormant during unfavorable conditions, such as drought or cold winters. They store energy in underground tubers, allowing them to re-emerge when conditions are more favorable. Some species also exhibit adaptations to specific habitats, such as those growing on rocky slopes developing extensive root systems for anchorage and water absorption. Many species can thrive in relatively deep shade, demonstrating an adaptation to low-light conditions.
Propagation Methods
Arisaema can be propagated by several methods, including:
- Seed: This is a slow method, as seeds can take several years to germinate and reach maturity. Fresh seeds are best and require a period of cold stratification.
- Division: Mature plants can be carefully divided when dormant, separating the tubers and replanting them. This is a more reliable method than seed propagation.
- Cormlets: Some species produce small cormlets (offsets) around the main tuber. These can be detached and planted separately.
Toxicology
Arisaema plants are highly toxic due to the presence of calcium oxalate crystals throughout the plant, especially in the tuber and foliage. Ingestion can cause immediate and intense burning pain and swelling of the mouth, throat, and stomach. Difficulty swallowing and breathing can also occur. Contact with the skin can also cause irritation. For humans, ingestion is rarely life-threatening, but medical attention should be sought. For pets like cats and dogs, ingestion can cause similar symptoms. Veterinary care is recommended if a pet ingests any part of the plant. Keep away from children and pets.
Common Problems
Pests:
- Aphids
- Spider mites
- Slugs and snails
Diseases:
- Tuber rot (due to poor drainage or fungal infection)
- Leaf spot
Other:
- Failure to thrive (often due to insufficient light or poor soil)
- Yellowing leaves (can be caused by overwatering or nutrient deficiencies)
- Dormancy issues (premature or delayed dormancy due to improper care)
Rarity & Value
Rarity:
Several factors can contribute to the rarity of specific Arisaema species. Slow growth rates, coupled with difficult propagation, contribute to their scarcity. Limited natural habitats, often restricted to specific regions or elevations, make certain species exceptionally rare. Also, some species possess unique variegation or morphological traits that collectors highly desire and can substantially increase its market demand and reduce its overall availability.
Value:
The value of an Arisaema specimen is affected by several factors. Size and maturity play a role, with larger, well-established plants commanding higher prices. Variegation, especially stable and striking patterns, dramatically increases value. The provenance (origin or documented history) of the plant can also be significant, particularly for rare or unusual species. Finally, current collector trends and demand greatly influence market value. Plants that are “trending” within the plant collecting community will often command higher prices due to increased competition among buyers.
