The term “lily” commonly refers to elegant, fragrant blooms found in gardens and floral arrangements. However, many plants share aesthetic similarities but are not botanically related to true lilies. Understanding scientific classification is key to distinguishing popular perception from the actual number of distinct lily kinds.
The True Lilies
True lilies belong exclusively to the genus Lilium, part of the Liliaceae family. These plants grow from scaly bulbs, composed of fleshy scales lacking a protective outer tunic. Their stems are unbranched, typically bearing leaves arranged in whorls or spirally.
Their flowers feature six tepals, as sepals and petals are indistinguishable. These tepals can be recurved, trumpet-shaped, or bowl-shaped, displaying a wide range of colors and patterns. Flowers vary in arrangement, appearing in racemes, umbels, or as solitary blooms.
Within the Lilium genus, botanists recognize several divisions based on horticultural characteristics and genetic lineage. These include Asiatic hybrids, known for upright, often unscented flowers; Oriental hybrids, prized for large, fragrant blooms; and Trumpet lilies, featuring distinctive trumpet-shaped flowers. Other divisions include Martagon lilies, with unique recurved petals, and American native lilies, adapted to specific regional conditions.
Plants Commonly Mistaken for Lilies
Many plants are colloquially called “lilies” due to their appearance or common names, though they do not belong to the Lilium genus.
- Daylilies (Hemerocallis) have fleshy roots, not true bulbs, and their flowers typically last only one day.
- Calla Lilies (Zantedeschia aethiopica) are arums with a spathe and spadix structure, not true petals, growing from rhizomes.
- Water Lilies (Nymphaea) are aquatic plants rooted in soil, with leaves and flowers floating on the water’s surface.
- Peace Lilies (Spathiphyllum) are indoor plants with white, leaf-like spathes surrounding a central spadix, members of the Araceae family.
- Peruvian Lilies (Alstroemeria) are recognized by their speckled petals and grow from tuberous roots, classifying them in the Alstroemeriaceae family.
- Lily of the Valley (Convallaria majalis) produces small, bell-shaped, fragrant flowers on an arching stem, but is a member of the Asparagaceae family.
The Count: How Many Species Exist
The Lilium genus includes approximately 100 to 110 recognized species worldwide. This count can fluctuate as taxonomic research refines classifications, leading to reclassification, discovery, or re-evaluation of species based on genetic studies.
True lily species are predominantly found in temperate regions of the Northern Hemisphere. Their native range spans Europe, Asia, and North America, contributing to significant variation in forms, colors, and growth habits.