Antirrhinum

( an - tihr - RYE - num )

At-A-Glance Information

Commonly called Snapdragon, Dragon Flower, Toadflax, or Dogflower, this genus contains perennial (commonly treated as annual) species that need full sun and regular water to perform well in the landscape. Brightly-colored flowers attract butterflies and other pollinators like bumblebees to gardens. Snapdragons are among the best plants to be included in sunny borders and for cutting for use in fresh arrangements. They have deep green leaves and flowers packed on to spikes, at their best in spring and early summertime. Use Snapdragons in mixed beds and borders, along pathways, or in containers and window boxes.

Antirrhinum species and Varietals

The genus Antirrhinum includes about 30 species, and is a member of the plant family Plantaginaceae (previously Scrophulariaceae). There are three accepted sub-genera: Antirrhinum (Old World species), Orontium (Mediterranean species), and Saerorhinum (New World species). The genus name is derived from the Greek words for front or protruding (anti) and snout or nose (rhinon). Snapdragons grow best in USDA hardiness zones 7-11 or Sunset growing zones A1-A3 and 1-24. Growing zones vary somewhat depending on the species cultivated; for more information, see the species descriptions below. To find your zone, click here: Zone Map.

Antirrhinum hispanicum (Spanish Snapdragon, La Boca de Dragon, Creeping Snapdragon, Perennial Snapdragon)
This species is native to southeastern Spain, and produces foliage and stems with hairs. Flowers are commonly white, pink, or yellow. These plants generally reach between 12 to 14 inches tall at maturity. This species does well in USDA hardiness zones 5a-8b.
Antirrhinum majus (Common Snapdragon, Great Snapdragon, Lion's-Mouth, Rabbit's Mouth, Bonny Rabbits, Calf-Snout, Toad's Mouth, Bulldogs, Lion's-Snap)
This species is the most commonly cultivated in western gardens, and has myriad varieties available at nurseries. Flowers come in a wide range of colors, and can be single, semi-double, or double. Height ranges from a foot tall to two and half feet tall. Common Snapdragon plants grow well in USDA hardiness zones 6-11. Varieties are listed and described below:
'Bicolor'
Variously bicolored flowers on 6-8 inch tall plants.
'Chantilly'
This group contains large double flowers of many different colors.
'Chinese Lanterns'
Trailing snapdragons great for hanging baskets.
'Candy Showers'
Snapdragons with a trailing habit.
'Doubleshot'
Antirrhinums with double blooms.
'Floral Carpet'
​('Magic Carpet')
Dwarf plants to 6-8 inches tall.
'Floral Showers'
6-8 inch tall flowers in various colors, great for containers.
'Kim'
A wide range of flower colors available on 6-8 inch tall plants.
'La Bella'
To 1.5 feet tall, with a variety of flower colors.
'Liberty'
​​To 15 inches tall with various flower colors.
'Madame Butterfly'
With double flowers, to 1-2 feet tall.
'Montego'
Dwarf Snapdragons to just 8 inches tall.
'Princess White with Purple Eye'
​To 1-2 feet tall.
'Rocket'
To 2.5 to 3 feet tall in various colors.
'Snappy'
A line of Snapdragons with a wide range of multi-colored flowers.
'Topper'
Flowering stems to 2.5-3 feet tall; great for cut flowers.

Antirrhinum siculum (Sicilian Snapdragon, Wall Snapdragon)
This species of Snapdragon is considered to be a wildflower, and has simple, narrow leaves. These plants reach about 16 inches tall at maturity, and have beautiful cream to yellow flowers with reddish-pink markings. Best in USDA hardiness zones 8a-10b.

Antirrhinum tortuosum (Antirrhinum majus tortuosum)(Greater Snapdragon)
This pink-flowered species is considered a wildflower, and grows well in rocky, sandy areas in full sun. These plants are native to the Mediterranean and Europe. Greater Snapdragon plants thrive in USDA hardiness zones 7-11.

Caring for antirrhinum

Antirrhinum, or Snapdragon, plants can be purchased as starts from a reputable nursery, and are also available in a wide range of heights and flower colors as seed. Seed can be started indoors 8-10 weeks before the last frost date of the region or direct-sown into the garden when soil temperatures reach 55 to 60 degrees Fahrenheit. The spot that you plant your Snapdragon will depend on the height of the plant purchased. Dwarf plants (those 6-9 inches tall) are best for edging, fronting beds, window boxes, and containers. Plants that are between 9 and 12 inches do well as edging, as well, or planted amongst other annuals in small beds. 1-2 foot tall plants are most popular, and have a variety of uses, and 2-3 foot tall plants are used towards the back of mixed beds or in cut flower gardens. No matter the height, plant Snapdragons in full sun to partial shade; they will flower more profusely the more sun they get. These flowers should be receiving at least 6 hours of direct sunlight each day for best performance, but do appreciate some late afternoon shade when temperatures are at their peak. Ensure that soil is well-draining and that it has a pH of between 6.2 and 7.0 (acidic to neutral). If your soil is heavy or clayey, it is a good idea to amend with plenty of organic material before installing these flowers to improve soil structure and tilth.  Apply a layer of mulch around the planting area to suppress weed growth, maintain consistent soil temperatures, and increase soil moisture retention. Keep soil consistently moist but not waterlogged, watering deeply whenever the top inch of soil feels dry. Avoid providing water with overhead sprinklers, as this may cause issues with fungal diseases.

Fertilize yearly in early springtime with an application of 2 inches of compost around the base of plants. Pull mulch back before applying, work the compost gently into the soil a bit, water it in, and then replace mulch. To prune, trim back leggy or overgrown stems to promote a bushier growth habit and to maintain the plant's natural shape and neatness. Cut back by about 1/3 at the beginning to the middle of summertime to rejuvenate them for a fresh flush of growth. In mild-winter climates, these plants may continue their bloom through winter into the next spring and summer and be treated as perennials. In cool-winter climates, they are typically treated as annuals. Seedlings can be pinched back every so often starting when they have produced 4-6 true leaves to encourage a bushier habit and increased blooms.

Growing Antirrhinum in Containers
Antirrhinum flowers can be grown in the ground or in containers. Choose a container that is slightly larger than the root ball, and fill with a well-draining potting mix amended with organic matter or compost. Apply a layer of mulch over the top to suppress weed growth, maintain consistent soil temperatures, and increase soil moisture retention. Snapdragons grown in containers will need more frequent irrigation than those grown in the ground. As a general rule of thumb, water whenever the top inch or two of soil feels dry to the touch. These flowers are typically used as seasonal color or annual plantings, pulled at the end of the growing season and re-planted in the next. In warm temperate regions or warmer zones, they can be used as perennials.

Harvesting Antirrhinum
Snapdragons, or Snaps, are commonly cultivated for their colorful spikes of blooms. They are one of the most productive early-season bloomers in the cutting garden, and are cut-and-come-again flowers; the more they are harvested, the more blooms are produced. The best varieties for cut flowers are those that feature long, straight stems. Taller varieties are preferred because they can be cut to a wider range of heights. It is recommended for an even harvest to succession sow Snapdragons, planting seeds every few weeks during the early growing season. Harvest flower spikes when at least 2-5 flowers on the spike are opened. Unopened buds may wilt in the vase. The best time of the day to harvest cut flowers is in the morning, after the dew has dried but before the heat of the day sets in. Cut stems at their base using sharp, clean shears or snips and drop them into a bucket of cool water. They have a vase life of between 5 and 16 days if properly cared for.

Propagation

Antirrhinum can be propagated either by using cuttings or from seed. To ensure that your propagated plant will have the exact same qualities and characteristics as the parent plant, use the cutting method. If you would like to experiment and see what plant you can grow from seed, just keep in mind that it will not necessarily be the same as the parent plant. To propagate your plant, follow the instructions below:

Propagating Antirrhinum by Cutting
  1. Gather your materials. You'll need a clean, sanitized, sharp pair of garden shears, rooting hormone, a pencil, and a 3-inch pot filled with well-draining compost or other organic material. If you don't have any potting medium on hand, you can make some. Just mix together equal parts (by volume) moss peat and horticultural-grade sand or grit sand.
  2. In spring or early summertime, choose the plant that you'd like to propagate. Ensure that this plant has had a good watering the night before, as this will improve the chances your cutting will take root. Cut one or more 6 inch portion(s) of the end of a non-blooming branch and strip the leaves off of the lower half. Make a hole in your planting medium by pushing your pencil into the soil. Dip the end of the stem in rooting hormone, and plant it in your pot. Fill in soil around the cutting to support it, but do not pack it down too much.
  3. Moisten with water, and ensure that the pot has good drainage. Your pot should be kept in warm, sunny conditions indoors (and not in direct sunlight). Water whenever your soil is dry under the top layer. After about four to six weeks have passed, your cutting should be rooted. When you notice new growth, you'll know you have roots. 
  4. Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring, when you can transplant it to its new home. Ensure that the last frost of the year has occurred before doing this, as it can seriously damage your new shrub.

Propagating Antirrhinum by Seed
  1. Keep in mind that the plant you get from seed will not necessarily mimic all of the characteristics of the parent plant. To propagate by seed, you will need a paper bag, a pot or tray filled with well-draining compost or other organic material, a spray bottle and a fork. If you don't have any potting medium on hand, you can make some. Just mix together equal parts (by volume) moss peat and horticultural-grade sand or grit sand. You will also, after a few weeks, need individual 3-inch pots for each seedling that grows.
  2. Harvest your seeds. The seed pods on these flowers look like tiny skulls, and readily release seeds when dry. Cut the flower spikes off of the plant and place them in a container or paper bag. This will keep the seeds contained as you harvest more flower spikes. Once at a  clean workspace, separate the seeds from the plant parts. They are very tiny, so take care when handling them.
  3. In late summertime or early springtime, water your prepared seed tray or pot filled with soil, and ensure that good drainage is occurring. Place your seeds in your prepared pot or seed tray about a quarter inch to a half-inch under the soil surface. Cover them with soil and water with your spray bottle. Place your tray of seeds in a warm area that receives bright, indirect light. A greenhouse is the most ideal climate, but a planting tray inside a window will do as well. Germination usually takes 7-14 days from sowing. Once you begin to see seedlings sprout and they are able to be handled, transplant them to their own individual 3-inch pots, filled with the same potting medium as described in Step 1. Loosen the seedlings from the potting medium by digging down with the tines of your fork about an inch and a half, gently working the seedling up until it is out. Then, replant the seedling in its individual pot.
  4. Keep the seedling's potting medium moist, but not wet, by spraying the soil with your spray bottle. Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring (after the danger of frost has passed), when you can transplant it to its new home.
Dried seed pods of an Antirrhinum plant, ready to spill their contents. They are said to look a bit like small skulls.
Antirrhinum seeds are very small; it is recommended to use a container while working with them so as not to lose them.

Problems and Pests

Snapdragon plants are generally pest and disease free, though they may occasionally suffer from the following issues:
  • Spider Mites
  • Aphids
  • Powdery Mildew
For information on how to deal with these plant issues, consult the following pages:
​

Gallery

Plant Snapdragons in mixed beds; here they are planted amongst Dahlia, Strawflower, and English Daisy.
Snapdragons come in a variety of heights, making them perfect additions to any planting. Here, they are featured behind a bed of Calibrachoa.
Here, Snapdragons provide a middle-height row between low-growing Dianthus and taller Delphinium.
Cottage gardens are common places to find Snapdragons, nestled amongst plants like Cransebill, Miniature Roses, Oregano, and Pansies.
Snapdragons provide pops of color in lawn borders. Here, it is planted behind rows of Dusty Miller and Lobelia.
This informal, relaxing garden features Snapdragons, Chartreuse Sweet Potato Vine, Miscanthus, Epilobium, and Sweet Alyssum.

Videos

How to grow Snaps from seed.
All about Snapdragon plants.
How to grow Snapdragons successfully, from start to finish.
How to grow and care for Snapdragons.
Using Snapdragons in fresh flower arrangements.
Learn how to pinch your Snaps to encourage more blooms.

Resources

How to Grow Snapdragons (Antirrhinum)
How to Grow and Care for Snapdragon
Planting Snapdragons in the Garden: How to Grow Snapdragons
How to Grow and Care for Snapdragon Flowers
How to Propagate Snapdragon from Cuttings
Wikipedia: List of Antirrhinum species
Wikipedia: Antirrhinum
The New Sunset Western Garden Book: The Ultimate Gardening Guide (2012) - Pages 155 - 156, Antirrhinum majus (Snapdragon)