Common moonseed (Menispermum canadense) is a flowering plant that’s indigenous to eastern North America. Common moonseed fruit looks suspiciously like grapes, but every part of the plant is toxic to humans. The two can be distinguished by checking the seeds: moonseeds have a single crescent-shaped seed, while grape seeds are round.
I. Appearance and Characteristics
Menispermum canadense, the Canadian moonseed, common moonseed, or yellow parilla, is a flowering plant in the family Menispermaceae, native to eastern North America, from southern Canada south to northern Florida, and from the Atlantic coast west to Manitoba and Texas. It occurs in thickets, moist woods, and the banks of streams.
It is a woody climbing vine growing to 6 meters (20 feet) tall. The leaves are palmately lobed, 5–20 centimeters (2–8 inches) in diameter with 3–7 shallow lobes, occasionally rounded and unlobed. The fruit are produced in 6–10 cm (2+1⁄4–4 in) diameter clusters of purple-black berries, each berry is 1–1.5 cm (1⁄3–2⁄3 in) in diameter. The seed inside the berry resembles a crescent moon, and is responsible for the common name. The fruit is ripe between September and October, the same general time frame in which wild grapes are ripe. Both the leaves and fruit resemble those of grapes; confusion can be dangerous as moonseed fruit is poisonous.
The root is a rhizome, so one specimen can form colonies of genetically identical plants.
All parts of these plants are known to be poisonous. The principal toxin is the alkaloid dauricine. The fruit of Canada Moonseed are poisonous and can be fatal. While foraging for wild grapes one should examine the seeds of the fruit to make sure one is not eating moonseeds: moonseeds have a single crescent-shaped seed, while grapes have round seeds. Differences in taste should also be an indicator of whether or not a specimen is grape or moonseed, moonseeds have a taste that is described as “rank”. Also, the moonseed vine lacks tendrils, whilst the vine of the wild grape has forked tendrils.
II. How to Grow and Care
Common moonseed is a periennal vine that thrives in woodland settings, indicative of its adaptability to a range of conditions. Key care points include ensuring partial to full shade and providing a well-draining soil, mimicking its natural habitat. Although moisture levels should be maintained, common moonseed is generally resilient and can withstand periods of neglect, making its care relatively straightforward.
Sunlight
Common moonseed flourishes optimally under partial sun conditions, where it enjoys diffused or dappled light with moderate intensity and indirect exposure. Deviations from this, such as prolonged periods in full sun, can be tolerated to a degree but may lead to consequences like scorched leaves or stunted growth, indicating stress from excessive light. Adaptively, common moonseed can adjust its leaf orientation to manage light absorption more effectively. Typically found outdoors, common moonseed should be positioned in locations that mimic its natural understorey habitat, such as the edges of woods and clearings where it receives filtered sunlight through the canopy above.
Watering
Common moonseed thrives in environments that mimic its native woodland settings, where it experiences periodic moisture followed by dry spells. This species is adapted to retain water efficiently, exhibiting a preference for moderate humidity and showing resilience during drier periods. Watering should be done once every three weeks, allowing the soil to dry out between sessions. As common moonseed is typically found outdoors, it’s important to consider how natural rainfall contributes to its watering schedule, especially as an understory plant in temperate climates where seasonal rain patterns dictate its growth cycles.
Fertilizing
To boost common moonseed’s growth and fruit production, use balanced nutrition fertilizers in the growing season, shifting to high nitrogen in early stages for vigorous growth. Apply fertilizer once a month at recommended rates on the label, halving the quantity for young plants. Avoid over-fertilizing, which can damage common moonseed. During dormancy, reduce fertilization frequency to support natural cycles. Liquid fertilizers allow precise application. Protective gloves ensure safe handling, preventing direct contact with common moonseed.
Propagation
To propagate common moonseed, gardeners should employ stem cuttings, a technique where portions of a stem with leaves are cut and planted to give rise to new individuals. It’s crucial to select healthy and mature stems for cuttings, ensuring they have at least one leaf node, as this is where root initiation is most likely. Once cut, the stems can be placed in a rooting medium that is kept moist but well-drained to promote root development. Care should be taken to maintain a stable environment with indirect light for optimal growth.
Transplanting
For common moonseed, the prime transplanting window is when spring awakens the soil. Choosing a spot with dappled sunlight optimizes growth post-transplant. Gentle handling of roots during the move safeguards its delicate nature.
III. Uses and Benefits
The Cherokee used moonseed as a laxative, and as a gynecological and venereal aid. The root was used for skin diseases. The Lenape used it in a salve for sores on the skin. It has been used for a variety of medicinal uses by Americans of European descent.