The common name “Lily of the Valley” often leads to confusion about its botanical classification. Despite its delicate appearance and popular association with lilies, this plant is not a true lily. Many assume a direct botanical relationship due to the shared name and similar aesthetic appeal. This article clarifies the precise botanical standing of Lily of the Valley and highlights the distinct characteristics that set it apart from true lilies.
The Definitive Answer: Not a True Lily
Lily of the Valley (Convallaria majalis) is not a true lily. True lilies belong to the genus Lilium within the Liliaceae family. Convallaria majalis is classified in the Asparagaceae family.
Historically, Lily of the Valley’s classification has shifted, previously being placed in its own family, Convallariaceae, or within Ruscaceae, and even earlier, grouped with lilioid monocots in the broader Liliaceae family. This taxonomic shift reflects advancements in botanical understanding.
True lilies are herbaceous, perennial plants that grow from scaly underground bulbs. The genus Lilium encompasses about 100 species, primarily found in temperate regions of the Northern Hemisphere.
Unpacking the Botanical Differences
Significant botanical features differentiate Lily of the Valley from true lilies. One primary distinction lies in their root structures. True lilies typically grow from scaly bulbs, which are underground storage organs. In contrast, Lily of the Valley spreads extensively through underground stems called rhizomes, forming dense colonies. These rhizomes allow it to spread aggressively and form a mat-like groundcover.
Their leaf arrangements also vary. Lily of the Valley typically produces two or three broad, basal leaves that emerge directly from the ground. True lilies, however, generally have leaves arranged along a central, upright stem.
The flowers themselves present clear differences. Lily of the Valley features small, bell-shaped, pendulous flowers arranged in a one-sided raceme on a leafless stalk. True lilies display larger, often prominent flowers that can be trumpet, funnel, or bowl-shaped, with six distinct petal-like segments (tepals), and are typically borne at the top of a stiff stem.
Further differences are found in their fruit. After blooming, Lily of the Valley produces small, globoid orange-red berries, each containing one to six seeds. True lilies, conversely, develop dry, three-celled capsules as their fruit. Lily of the Valley typically reaches 6 to 12 inches tall, while true lilies are upright plants that can range from one to eight feet.
Beyond the Name: Key Characteristics of Lily of the Valley
Lily of the Valley (Convallaria majalis) is a woodland flowering plant, native to Europe and western and northern Asia, and has naturalized in parts of North America. It thrives in shaded or partially shaded environments with moist, organically rich soil, often found under trees or in woodlands. This perennial is prized for its intensely sweet and distinctive fragrance, which is often used in perfumes.
Its stems usually bear two or three large, dark green leaves. A significant characteristic of Lily of the Valley is its toxicity. All parts of the plant, including its leaves, stems, flowers, and attractive red berries, are poisonous if ingested.
The plant contains cardiac glycosides, such as convallarin, convallamarin, and convallatoxin. These compounds can affect the heart, and ingestion can lead to symptoms like nausea, vomiting, weakness, altered mental status, and irregular heart rhythms, which can be severe or even fatal. Due to this toxicity, caution is advised when planting it, especially in areas accessible to children and pets.