How to Grow and Care for Snapdragon Plants

Snapdragon flowers
Ian Lee/flickr/CC By 2.0

Overview and Description

Snapdragons have tall spikes of brightly colored flowers that bloom profusely in cooler weather. Most are intensely colored and real standouts in the spring or fall garden. Snapdragon flowers start blooming at the bottom of the stalk and work their way up, making for a long period of bloom.

The Latin name, Antirrhinum, means "like a snout" and refers to the seed pod's resemblance to a calf's nose.

How do such charming flowers wind up with such ungracious names?

The common names all derive from the way the flowers resemble opening mouths when they are pressed on their sides. The openings of the flowers are snapped tightly shut and require more pressure to open than a honeybee can provide, so snapdragons rely on heavier bumble bees for their pollination.

Leaves: The alternate, lanceolate leaves are arranged in a spiral around the stem.

Flowers: The flowers come in just about every shade, except true blue. Some are vibrant bold tones, some are soft pastels and some are subtly shaded bi-colors.

CAUTION: All parts of snapdragon are poisonous if ingested.

Latin Name

Antirrhinum majus

Common Name

Snapdragon, Dog's Mouth, Lion's Mouth, Toad's Mouth

Hardiness Zones

Snapdragons are tender perennials that are only hardy to about USDA Hardiness Zones 8 or 9. In most areas, they are commonly grown as annuals.

Even when they do over-winter, they never seem to bloom as robustly as they did in their first year, which leads many people to think they are biennial, but they should form seed pods in their first year. If you're lucky, they may even self-sow.


They will bloom most profusely in full sun to partial shade, in the spring.

Once the temperature heats up, they may stop blooming altogether. Planting them in partial shade and keeping them well watered will help them make it through the summer, to begin blooming again in fall. However, they are quick to get established and it can be just as easy to replace your snapdragon plants each season.

Mature Size

There are tall varieties and dwarf varieties and just about everything in between. Check the label or packet of the variety you are choosing.

Dwarf plants mature at a height of about 6-15 in. and from a dense, bushy plants with lots of flower stalks.

Tall varieties tend to be less bushy in habit, reaching a height of 30-48 in.

Some varieties bridge the two extremes, growing to a mid-sized 15-30 in. Of course, the actual size and fullness of the plants will also depend on growing conditions.

Bloom Period

Snapdragons are at their best in cool weather. They can repeat bloom throughout the season, but do best in the cool of spring and fall and throughout the winter, in mild climates. Deadheading can increase the amount of buds that are set, but since the flower stalks begin blooming from the bottom up, they have a fairly long bloom duration anyway.

Suggested Varieties

They're continually coming out with new snapdragon series.

Most are sold as multi-color blends, but you can sometimes find individual colors in both seed and seedling. Some of the more popular series include:

  • Arrow™ Formula Mix - Vivid colors on strong, branching stems. Grows 2' tall.
  • La Bella Mix - A nice blend of colors from pale to bronze to deeply saturated. Grows 12-18" tall.
  • Rocket Mix - a dependable multi-colored series that grows to about 2-3' tall.

Design Suggestions

Their spiky, bright colored flower stakes make a nice foil for the cooler shades of most spring flowers, like Brunnera and Bleeding Heart. Planted in clusters, they can help a border transition from the spring ephemerals to peak heat season.

The pale yellow varieties are the easiest to blend into a mixed border and work nicely with pinks, purples, and even reds.

Breeders have been playing with snapdragons for a few years now and there are trailing and creeping varieties becoming more widely available.

These are great filler plants for containers, baskets and tucked into walls.

Growing Tips

Soil: Snapdragons like a neutral soil pH, between 6.2 and 7.0. As short-lived plants, they are not heavy feeders, but adding organic matter will help keep them healthy and blooming.

Planting: Snapdragons can be winter sown, meaning you can toss the seeds out in late fall or even on top of snow, and most will germinate in the spring.

However, snapdragons are most often either started indoors, 8 - 10 weeks before the last frost date, grown from cuttings or purchased as seedlings. When starting from seed, simply press the seed on the surface of the potting soil. Snapdragon seeds need light to germinate.

When seedlings have developed about 6 true leaves, pinch the top of the stem off, to encourage branching and a fuller plant. You can do this with purchased seedlings too.

Transplant snapdragons outdoors a couple of weeks before your last frost date. Snapdragons can handle a light frost or two.


Regular deadheading will keep your snapdragons blooming longer. They won't need much care early in spring, but mulching to keep the soil cool and moist can help them handle summer better.

Snapdragons are tender perennials and may die off in colder climates. If they do survive the winter, prune them back by about 1/3, to encourage new growth. Don't be too disappointed if they don't last long. Snapdragons tend to go downhill after their first year and it's best to start fresh every year. Many varieties will self-seed and come back on their own, although they won't always look like the original plants you planted.

Some of the taller varieties will need staking.

Pests and Problems

Snapdragons are affected by few pests or diseases. Rust and other fungal diseases can be a problem, especially in wet seasons. If you live in a damp or humid area, look for resistant varieties. Snapdragons may also attract aphids.