
Antirrhinum
Antirrhinum
About Antirrhinum
The Snapdragon, botanically designated as Antirrhinum majus and belonging to the family Plantaginaceae (the plantain family, formerly grouped under Scrophulariaceae), is an exceptionally charming and iconic herbaceous perennial. Native to the rocky screes, ancient ruins, and coastal cliffs of the Mediterranean region—with high concentration across Spain, Italy, and North Africa—this beautiful plant has been cultivated in gardens since ancient Roman times. It is celebrated worldwide for its towering flower spikes and its highly unique, touch-sensitive blossoms.
Cultivated primarily as a cool-season annual, the Snapdragon grows in dense, upright spikes that range in height from 6-inch compact dwarfs (ideal for bedding and pots) to 4-foot towering giants (highly prized as florist cut flowers). It features smooth, lance-shaped, deep green leaves arranged spirally along sturdy stems. From early spring through autumn, the stem tips erupt in magnificent, dense spikes of tubular, two-lipped flowers. When the sides of an individual blossom are gently squeezed, the lips snap open and shut like a miniature dragon's jaw, revealing a colorful throat.
The reproductive morphology of Antirrhinum majus is defined by the zygomorphic botanical floral formula % ⚥ K(5) [C(5) A4] G(2). This formula reveals that the flowers are bilaterally symmetrical (zygomorphic) and bisexual. The calyx is composed of 5 fused, protective sepals, and the corolla features 5 fused petals that form a two-lipped, closed tube (personate corolla). The androecium consists of exactly 4 stamens in two pairs of unequal length (didynamous) fused to the corolla tube, while the gynoecium contains 2 fused carpels with a superior ovary.
Horticulturally, Snapdragons are exceptionally hardy and straightforward to grow, thriving in cool climates where other annuals struggle. They perform best in full sun to partial shade, requiring at least 6 hours of direct daily sunlight to prevent the flower spikes from leaning. They prefer rich, organic, moist, and well-draining soils; waterlogged conditions will rapidly cause root rot. They are highly frost-tolerant and bloom beautifully in spring and autumn when temperatures are between 50°F and 70°F, while their blooming will go dormant under high summer heat.
The genus name Antirrhinum comes from the ancient Greek words 'anti', meaning 'like' or 'as,' and 'rhis', meaning 'nose' or 'snout,' directly referencing the snout-like shape of the individual blossoms. Known in Sanskrit as Simhamukha (सिंहमुखः, meaning 'lion's face') and in Hindi as Nakshe phool (नक्शा फूल) or Dog Flower (डॉग फ्लावर), it holds high ornamental value in Asia. In Victorian flower language, snapdragons represented a complex mix of charming grace, inner strength, and playful presumption.
For pet owners and veterinarians, the Snapdragon represents an exceptionally safe, premium, and pet-friendly choice. *Antirrhinum majus* is classified as completely NON-TOXIC to cats, dogs, and horses by the ASPCA. If an active pet runs through, plays with, or nibbles on the colorful spikes, there is absolutely no danger of toxic chemical poisoning. For detailed instructions on selecting safe garden bedding plants and pet-friendly landscaping, visit our specific Pet Guard registry page. (Note: Dried seed pods resemble tiny human skulls, adding dry floral interest.)
Snapdragon is occasionally confused with Toadflax (Linaria). It is easily distinguished because snapdragons possess much larger, fleshy, closed blossoms that require heavy pollinators like bumblebees to push open, whereas Linaria has much smaller, spurred flowers. It is an outstanding choice for vertical accents in borders, beds, and window boxes; we recommend pairing it beside other non-toxic classics like the golden Marigold or colorful Phlox. To discover more cool-season annual combinations and planting guides, browse our Flower Identifier.
Floral Formula & Features
Bilaterally symmetrical, bisexual, 5 fused sepals, 5 fused petals forming two-lipped corolla, 4 stamens (didynamous - 2 long, 2 short) fused to corolla tube, 2 fused carpels with superior ovary
- Scientific Name & Classification: Antirrhinum majus (Plantaginaceae). Commonly known as Snapdragon, Dragon's Mouth, and Lion's Mouth.
- Identification Markers: Upright flowering spikes, smooth lance-shaped leaves, and two-lipped tubular flowers that snap open and shut when squeezed.
- Floral Formula (% ⚥ K(5) [C(5) A4] G(2)): Bilaterally symmetrical, bisexual flowers with 5 fused sepals, 5 fused petals, 4 didynamous stamens, and superior ovary.
- Growing Requirements: Full sun to partial shade; prefers rich, moist, exceptionally well-drained soil. Extremely frost-tolerant, thriving in cool spring and fall (Zones 7-10).
- Cultural Significance: Sanskrit 'Simhamukha' means lion's face. In Victorian language, it symbolized charming grace. Dried seed pods resemble miniature skulls.
- Safety & Toxicity: NON-TOXIC & PET-SAFE. 100% safe for cats, dogs, and horses. Listed as a premier ASPCA-safe bedding annual for residential spaces.
- Common Look-alikes: Confused with Linaria (Toadflax), but distinguished by its much larger, fleshy, closed flowers that snap shut when released.
- Internal Links: Adds stunning height to cottage borders when planted alongside other pet-safe annuals like Marigold or Phlox; check our Flower Identifier.
Names in Different Languages
Toxicity & Safety
Frequently Asked Questions
What is Floral Formula?
A floral formula is a symbolic representation of a flower's structure using letters, numbers, and special symbols. It provides a concise way to describe the arrangement and number of floral parts.
This formula describes the flower's symmetry, sepals, petals, stamens, and carpels in a standardized format.
Formula Sequence
- Bract: Br or Ebr
- Bracteole: Brl or Ebrl
- Symmetry: % (Radial) or ⊕ (Bilateral)
- Sex: ♀ (Female), ♂ (Male), or ⚥ (Bisexual)
- Calyx/Sepal: K<number> (Free or Fused)
- Corolla/Petal: C<number> (Free or Fused)
- Androecium: A<number> (Free or Fused)
- Gynaecium: G<number> (Superior or Inferior Ovary)
Symbol Meanings
- Numbers: Indicate quantity of parts
- Parentheses (): Parts are fused together
- Plus (+): Parts in different whorls
- Underline: Superior ovary position
- Overline: Inferior ovary position
- ∞: Numerous parts (too many to count)
Understanding floral formulas helps botanists quickly identify and classify flowers based on their structural characteristics.






