How to Grow Antirrhinum Plants in your Garden

Article by Dean Ravenscroft, Ph.D. - Updated 21st Nov 2023

In this Gardener's HQ guide, we'll explore cultivating Antirrhinum plants in your garden, indoor spaces, and other settings.

Snapdragon, and Dragon Flower: Cultivation & Garden Use

The half hardy perennial Antirrhinum flowers from late spring through to the late autumn. Snapdragon is a sub-shrub.

It carries flowers that range in colour from vibrant red and orange through to pale pastel.

Brother Alfred Brousseau @ USDA-NRCS PLANTS Database. St. Mary's College of California.

Description of Antirrhinum

Antirrhinum ranges range in height from six inches (15 cm) for dwarf species to as high as 25 inches (65 cm) for taller varieties. Interestingly it is the taller varieties that are most sturdy with the dwarf varieties being quite floppy in nature.

Main Antirrhinum Plant Species

Antirrhinum majus

Antirrhinum majus (Common Snapdragon) is a beloved garden plant. It is known for its distinctive, dragon-shaped flowers. These come in a vast array of vivid colors. This species is noted for its tall, upright growth habit and lance-shaped, medium green leaves.

Antirrhinum majus by Carl E. Lewis.

Antirrhinum majus plants thrive in a location with full sun to partial shade, and requires a well-drained soil.

This plant is widely used in beds, borders, and containers. The taller varieties also make for excellent cut flowers as well.

Antirrhinum multiflorum

Antirrhinum multiflorum (Sticky Snapdragon) is a perennial plant. It is known for its dense clusters of small, two-lipped, snapdragon-like flowers. These come in shades of pink and purple. Its defining feature are its sticky, glandular hairs. These cover the stems and leaves.

Adapting well to sunny, rocky habitats, with a well-drained soil. It is most often used in rock gardens and in wildflower gardens. Its long blooming season enhances its garden appeal.

Antirrhinum siculum

Antirrhinum siculum (Sicilian Snapdragon) is a rare and beautiful plant that is characterized by tall spikes of large, pale pink to purple, open-mouthed flowers. Its attractive foliage consists of slender, lance-shaped leaves.

Best grown in well-drained soil and full sun, it is perfect for sunny borders, rockeries, and containers. It can add a unique Mediterranean charm to any garden setting.

How to Grow Antirrhinum

It is best to sow Antirrhinum on the soil surface under cold frames in the late summer. Ideally Snapdragon should be sowed indoors eight or nine weeks before planting out.

If growing indoors, seeds should be allowed two to three weeks to germinate; they should then be grown at a temperature of around 13 degrees Celsius.

Antirrhinum should then be planted outdoors in the autumn. Antirrhinum spacing should be from six inches (15 cm) for dwarf species to twelve inches (30 cm) for larger species.

They prosper in full sunlight, though they can also tolerate light shade if it is a necessity. The soil type is not that important but should not be too heavy; snapdragon prefers a richer soil of neutral pH.

Snapdragon by A. Gude.

Caring for Snapdragon Antirrhinum Species

Snapdragon is an easy plant to look after. Ideally they should be pinched back at the five or six leaf stage to facilitate a bushy growth habit.

Prior to flowering they require a couple of light feeds. When caring for Snapdragons it is important to deadhead plants following flowering to encourage further flowers.

Thus good Snapdragon flower care involves regular watering (without waterlogging), growing in a location with a full sun to partial shade exposure, and using a well-draining soil enriched with compost, remove spent flowers to encourage continuous blooming throughout the blooming season.

Common Questions

How many members does the Antirrhinum genus have?

The Antirrhinum genus consists of around 20 species, the most famous being Antirrhinum majus, commonly known as snapdragon.

Do members of Antirrhinum make a good garden or landscaping plant?

Yes, members of Antirrhinum, particularly snapdragons, make excellent garden plants due to their vibrant, uniquely shaped flowers and tall, upright growth.

Which Antirrhinum species are most frequently grown by gardeners?

The most commonly grown species is Antirrhinum majus or snapdragon, which is beloved for its colorful, dragon-shaped blooms.

Are members of the Antirrhinum fragrant?

Yes, many Antirrhinum species, particularly snapdragons, have a light, sweet fragrance, particularly in the evening.

What is the normal Antirrhinum height

Standard Snapdragons typically grow to a height of 0.5–1 meters (18 to 32 inches). Dwarf varieties can be as short as 15 cm (6 inches), whilst taller varieties may reach up to 1.2 meters (4 ft).

What is the perfect location to grow Antirrhinum?

Antirrhinum prefers full sun to partial shade and well-drained soil. It can tolerate a variety of soil conditions.

Is Antirrhinum invasive in the USA, if so in which states?

Antirrhinum is not typically considered invasive in the USA, though it can self-seed prolifically under the right conditions.

How cold can snapdragons tolerate?

Snapdragons are cool-season flowers and can readily tolerate frost and temperatures as low as -7°C (20°F). They will struggle if exposed to long periods of extreme cold temperatures.

How do I remove Antirrhinum from my garden?

Antirrhinum can be removed by pulling out the plants, ensuring to get as much of the root system as possible to prevent regrowth.

When to pinch snapdragons?

Snapdragons should be pinched when they reach about 5-6 inches (12 to 15 cm) in height. Do this in the spring. By pinching off the top set of leaves, the Snapdragon will branch out and become fuller. This in turn should lead to it producuing more flowers.

Summary

The Antirrhinum genus, commonly known as snapdragons, belongs to the Plantaginaceae family. This genus includes approximately 20 species, all famous for their vibrant and distinctively shaped flowers. Originating from rocky areas of Europe, the US, and North Africa, these annual or perennial plants are cherished by gardeners for the unique, dragon-mouth shape of their blooms and the rich array of colors they offer.

Snapdragons prefer full sun to partial shade and need well-drained soil to thrive. They are cool-season flowers, often blooming in the chill of early spring and late fall, when temperatures are mild. To ensure the longevity and abundance of blooms, regular deadheading is recommended. Due to their cold hardiness, they can survive frost and thus can be planted early in the season or in the fall in mild winter regions.

I hope that you enjoyed this guide on how to grow Antirrhinum plants. You may also enjoy the following Gardener's HQ growing guides: Growing Cymbalaria, Chelone, and Digitalis plants.