How to Grow Snapdragons

Snapdragons are a favorite among gardeners for their vibrant colors and unique, dragon-like blooms. These charming flowers, available in a wide array of hues from soft pastels to bold, striking shades, add a touch of whimsy and elegance to any garden. 

Growing snapdragons is an enjoyable and rewarding process, suitable for both seasoned gardeners and beginners. These resilient plants can thrive in various conditions, bringing life and cheer to gardens, balconies, and patios. With their long blooming season, snapdragons provide continuous beauty from spring through fall.

In this post, we will take you through the essential steps to successfully grow snapdragons, from propagation to planting and care. With their striking appearance and easy-care nature, these flowers are sure to become a beloved addition to your garden.

Scientific name	Antirrhinum majus
Common name	Snapdragon, dog’s mouth, lion’s mouth, toad’s mouth
Family	Plantaginaceae
Plant Type	Perennial, annual
Height	6-48 in. tall, 3-12 in. wide
Sunlight	Full sun
Soil	Moist, well-draining
Flower Color	White, yellow, pink, red, orange, purple
Flowering Season	Spring, summer, fall
Habitat	Mediterranean, Europe, Asia

Propagation

Propagation by Seeds

Collect seeds from mature, dried pods after the flowers have faded. Store the seeds in a cool, dry place until planting time.

Start seeds indoors 6-8 weeks before the last expected frost. Fill seed trays with a seed-starting mix. Sow seeds on the soil surface and lightly press them in; they need light to germinate. Mist the soil lightly with water.

Place the trays in a warm, bright location or under grow lights. Keep the soil moist but not waterlogged. Seeds should germinate in 10-14 days at temperatures around 65-75°F (18-24°C).

Once seedlings have 2-3 sets of true leaves, harden them off by gradually exposing them to outdoor conditions. Transplant them into the garden after the last frost date, spacing them 6-12 inches apart.

Note: Due to the free cross-pollination of snapdragons, seeds collected from a snapdragon may produce plants that differ from the parent.

 

Propagation by Cuttings

Select healthy, non-flowering shoots from a mature Snapdragon plant. Cut a 2-inch section of stem just below a leaf node. Remove the lower leaves, leaving only the top few sets.

Dip the cut end in rooting hormone to encourage root development. Insert the cuttings into pots filled with seed starter mix or potting soil. Cover the pot with a plastic bag or dome to maintain humidity around the cutting. Place the pots in a warm, bright location, but out of direct sunlight. Keep the soil moist but not waterlogged.

Roots should develop in 2-3 weeks. Once a good root system develops, remove the cover. Continue growing the cuttings in a bright window or under artificial lighting. Transplant the rooted cuttings outside around the time of the last frost in your area. Space them 6-12 inches apart in prepared soil.

Propagation by Root Division

Root division is suitable for perennial Snapdragons or those that have overwintered. Water the Snapdragon plant thoroughly the day before dividing to ensure the roots are well-hydrated. Carefully dig around the base of the plant with a spade or garden fork to avoid damaging the roots.

Lift the entire plant out of the ground, keeping as much of the root system intact as possible. Shake off excess soil to expose the root system. Use pruning shears or a sharp knife to divide the root ball into smaller sections. Each section should have several healthy roots and shoots.

Prepare the planting site or pots with well-draining soil mixed with compost. Plant each division at the same depth as the original plant, spacing them 6-12 inches apart. Water thoroughly to help the plants establish.

 

Growing Snapdragon Flowers (From Seeds)

Preparation

Choose types of snapdragon based on your needs:

Dwarf (6 to 15 Inches Tall)

• Floral Showers: perfect for edging and containers, available in various vibrant colors.
• Frosted Flames: variegated foliage and bright flowers in red, pink, and yellow.
• Magic Carpet: spreading habit ideal for ground cover and borders, with a mix of colors.
• Montego: early blooming, suited for pots and garden beds, in a broad color palette.

 

Medium or Intermediate (15 to 30 Inches Tall)

• Bridal Pink: soft pink blooms, ideal for mid-border plantings and bouquets.
• Liberty: sturdy stems, and vibrant colors, excellent for cut flowers.
• Lucky Lips: known for their unique lip-shaped flowers in various colors.
• Opus: upright growth with large blooms, great for flower beds.

 

Tall (30 to 48 Inches Tall)

• Chantilly: open-faced flowers in pastel shades, ideal for cutting.
• Maryland Plumblossom: with lavender-pink blooms, perfect for tall garden borders.
• Potomac: strong stems, and long-lasting blooms, excellent for cutting.
• Rocket: classic snapdragon with dense flower spikes in various colors.

 

Snapdragons prefer well-drained soil rich in organic matter and soil pH from 6.2 to 7.0. Use a sterile seed-starting mix to prevent disease.

Select a location that receives full sun to partial shade. Ensure good air circulation to prevent disease.

Purchase high-quality Snapdragon seeds from a reputable supplier. Store seeds in a cool, dry place until planting time.

 

Growing Indoors

For Upper and Middle South gardeners: Start seeds indoors under lights about eight weeks before the average last frost.

For Lower South, Coastal South, and Tropical South gardeners: Sow seeds at the end of September to plant Snapdragons in the garden by the end of November.

Add moistened seed-starting mix in clean seed-starting trays with drainage holes. Sprinkle Snapdragon seeds on top of the mix or sow evenly with a moistened toothpick. The seeds are very fine and need light to germinate. Press the seeds onto the moistened mix for contact, but do not cover them with soil or another mixture.

Place the trays under grow lights or fluorescent tubes, leaving the lights on for 14 to 16 hours daily. Ensure the lights are adjustable and positioned only a few inches away from the plants. Adjust the lights as the seedlings grow to keep them close to the plants.

Snapdragon seeds can take up to two weeks to germinate, so be patient. Mist with water frequently to ensure the seeds do not dry out, as they cannot be revived once dry.

As seedlings grow, you can water or mist less often because the roots will start obtaining water from a lower depth in the mix. Thin the seedlings by cutting the weakest ones at the base with manicure scissors to make room for the strongest plants.

 

Transplanting Outdoors

Gradually acclimate seedlings to outdoor conditions about 1-2 weeks before transplanting. Start by placing them outside in a sheltered location for a few hours each day, gradually increasing the time and exposure to sunlight.

Loosen the soil to a depth of 12-15 inches. Mix in 2-4 inches of compost to improve soil fertility and drainage. When true leaves have developed and it’s a few weeks before the average last frost, transplant the seedlings into the garden or containers.

Snapdragons can tolerate a light frost, so it is fine to plant them outside one or two weeks before the average last frost. Space plants 6-12 inches apart, depending on the variety. Plant them at the same depth they were in their pots.

Water thoroughly after transplanting. Apply a 2-3 inch layer of mulch around the plants to retain moisture, suppress weeds, and regulate soil temperature.

Tips: Plant marigolds alongside snapdragons to repel pests such as aphids and whiteflies, while adding complementary color to your garden.

 

Care for Snapdragon Flowers

Here are main requirements for growing snapdragon flowers:

• Prefer well-drained, fertile loamy soil with a pH between 6.0 and 7.5.
• Grow in full sun to partial shade, requiring at least 6-8 hours of sunlight daily.
• Water deeply 1 inch of water per week.
• Regular deadheading to encourage new blooms.
• Bumblebees pollinate snapdragon flowers, and they attract hummingbirds.

 

Light

Snapdragons need 6-8 hours of sunlight each day to thrive, preferring full sun to partial shade. In very hot weather, they might cease blooming. To help them endure summer heat, plant them where they get afternoon shade and keep the soil consistently moist; they often bloom again in fall.

 

Soil

Snapdragons prefer well-drained, fertile loamy soil with a pH between 6.0 and 7.5. This type of soil retains necessary moisture while allowing excess water to drain, preventing root rot.

Enhance soil fertility and structure by incorporating compost or organic matter, ensuring a healthy environment for snapdragons to thrive.

 

Water

Snapdragons need about 1 inch of water per week, requiring consistent moisture. Water deeply once or twice a week, preferably in the morning. Let the top inch of soil dry before watering again. Water near the plant’s crown and avoid overhead watering. Mulch to help retain moisture, especially during hot weather.

 

Temperature and Humidity

Snapdragons thrive in temperatures between 60°F to 75°F (15°C to 24°C) and prefer cooler conditions, with nighttime temperatures in the low 40s F and daytime temperatures in the low 70s F. They are hardy in USDA zones 7-11 but are often grown as annuals in cooler months.

Once established and hardened off, snapdragons can endure sub-freezing temperatures. Keeping them well-watered and adding pine straw mulch during cold spells helps them survive until warmer weather returns.

 

Pruning

Pruning snapdragons promotes bushier growth and more blooms. When the plant reaches about 4 inches tall, pinch back the top inch to encourage side shoots, enhancing flower production.

Use clean, sharp shears and make cuts at a 45-degree angle for precision. For taller varieties, pinching prevents flopping. Regularly deadhead spent flowers to stimulate continuous blooming.

 

Fertilizer

Apply a balanced fertilizer, such as NPK 10-10-10, monthly during the growing season. Use about 1 tablespoon per square foot, ensuring even distribution. Avoid excessive nitrogen to prevent weak stems. Fertilize when planting and again as blooms appear to support healthy growth and abundant flowers.

 

Staking

For tall snapdragon varieties, staking provides crucial support. Insert stakes near the plants and tie the stems loosely with soft twine to prevent flopping. This helps maintain an upright growth habit, especially during windy conditions or heavy blooms.

 

Pests and Diseases

Snapdragons can suffer from pests like aphids, spider mites, and caterpillars, which cause distorted growth and leaf damage. Monitor plants regularly and treat infestations with insecticidal soap or neem oil.

Diseases such as rust, powdery mildew, and root rot can also affect snapdragons. Rust appears as orange spots, while powdery mildew creates a white coating on leaves, hindering photosynthesis.

Ensure good air circulation, avoid overhead watering, and use fungicides for rust and powdery mildew. Prevent root rot by maintaining well-drained soil and removing affected plants.

 

Common Problems

Yellowing Leaves

This is caused by drought stress, nutrient deficiencies, or incorrect soil pH. Ensure consistent watering, especially during dry spells, and use mulch to retain moisture. Test and adjust soil pH to maintain an optimal range of 6.0 to 7.5.

 

Poor Growth

This problem can result from overcrowding, lack of nutrients, or heat stress. Thin seedlings to ensure good air circulation and reduce competition. Regularly fertilize with a balanced, all-purpose fertilizer and provide partial shade during extreme heat.

 

Wilting and Reduced Blooms

These are caused by extreme heat and insufficient watering. Provide afternoon shade in hot climates and ensure the soil is consistently moist but not waterlogged.

 

Harvest

For Fresh Flowers

Harvest snapdragons early in the morning when two-thirds of the flowers on the spike have opened. Pick the flowers when they are fully open but before they start to fade.

Use sharp, clean scissors or garden shears to make a clean cut at a 45-degree angle, ensuring minimal damage to the stems. Place the cut stems in a bucket of clean water immediately to keep them hydrated and fresh.

 

For Seeds

Allow some flowers to remain on the plant until they mature and form seed pods. Once the pods are dry and brown, carefully collect them. Open the pods and shake out the seeds, then spread them out to dry completely.

Store the dried seeds in a cool, dry place in labeled envelopes or containers for future planting.

 

Preservation

Gather small bunches of stems and secure them with a rubber band or string. Hang the bundles upside down in a cool, dry, and dark place with good air circulation. This method helps the flowers retain their shape and color. It usually takes 2-3 weeks for the flowers to dry completely.

By following these steps, you can dry snapdragon seed pods to create intriguing “skull” decorations that add a unique and creative touch to your decoration.

Growing snapdragons can bring vibrant colors and unique textures to your garden. Enjoy fresh arrangements, dried displays, and seed collection by following these guidelines for beautiful blooms throughout the seasons.