Hound's Tongue vs Larkspur Delphinium Plant Comparison

Compare these two plants side by side — care needs, key differences, and which is right for your home.

Hound's Tongue

Hound's Tongue

Cynoglossum officinale

VS
Larkspur Delphinium

Larkspur Delphinium

Delphinium spp.

Hound's Tongue

Hound's Tongue

Cynoglossum officinale

Hound's Tongue is a biennial or short-lived perennial herb, typically growing to 1-3 feet tall. It features a rosette of large, lance-shaped basal leaves in its first year, followed by an erect flowering stem in the second. The plant is characterized by its rough, hairy texture and distinctive reddish-purple flowers that bloom in the summer. The seeds are covered in small barbs, resembling a dog's tongue, which aid in their dispersal by clinging to animals. It is primarily an outdoor plant, valued for its unique appearance and historical medicinal uses, though it is now recognized as toxic.

Boraginaceae Europe and Asia; naturalized in North America
✨ Features: Unique seed dispersal mechanism (burrs), historical medicinal uses (though now discouraged due to toxicity)
📖 Read Complete Hound's Tongue Guide
Larkspur Delphinium

Larkspur Delphinium

Delphinium spp.

Larkspurs are annual or perennial herbaceous plants known for their tall, elegant flower spikes. They typically grow to heights of 1 to 6 feet, depending on the species and cultivar. The flowers come in a wide range of colors, including blue, purple, pink, white, and yellow. Larkspurs are primarily outdoor plants, prized for their striking vertical presence in gardens and borders. They are grown for their beautiful, showy flowers that attract pollinators.

Ranunculaceae Primarily Northern Hemisphere, including Europe, Asia, and North America
✨ Features: Attracts pollinators like bees and butterflies.
📖 Read Complete Larkspur Delphinium Guide

Quick Plant Comparison

Feature Hound's Tongue Larkspur Delphinium
Light Full sun to partial shade Full sun
Watering Every 1-2 weeks, depending on rainfall and soil drainage Every 3-7 days, depending on weather and soil drainage
Humidity 30-50% 30-50%
Temperature 10-25°C 15-24°C
Care Level Expert Expert
Growth Rate Moderate Moderate
Max Height N/A (Primarily an outdoor plant, not suitable for indoor growing) Rarely grown indoors, outdoor height 0.3-1.8 meters
Pet Safety ❌ Toxic To Pets ❌ Toxic To Pets
Soil Well-drained soil, tolerates a range of soil types including clay, loam, and sand Well-draining, fertile soil with a slightly acidic to neutral pH (6.0-7.0)
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 15 minutes weekly (primarily for monitoring spread and removing seed heads) 30 minutes weekly (weeding, watering, deadheading)

🔬 Botanical Information — Comparing These Plants

Hound's Tongue

Scientific Name Cynoglossum officinale
Family Boraginaceae
Native To Europe and Asia; naturalized in North America
Also Known As Houndstongue, Hound's Tongue, Gypsyflower
Leaves The leaves are lance-shaped to oblong, 10-30 cm long and 2-8 cm wide, with a rough, hairy texture. The basal leaves are larger than the stem leaves. The color is a dull green to grayish-green.
Flowers The flowers are small, reddish-purple to maroon, and arranged in scorpioid cymes (coiled clusters) along the flowering stem. They bloom in the summer (June-August). It does not flower indoors.

Larkspur Delphinium

Scientific Name Delphinium spp.
Family Ranunculaceae
Native To Primarily Northern Hemisphere, including Europe, Asia, and North America
Also Known As Larkspur, Delphinium
Leaves The leaves are deeply lobed and finely divided, giving them a delicate, fern-like appearance. They are typically green or bluish-green in color and arranged alternately along the stem.
Flowers Rarely flowers indoors. Outdoors, they produce tall spikes of spurred flowers in shades of blue, purple, pink, white, and yellow. The flowers bloom in summer.

📏 Size & Growth — Plant Comparison

Hound's Tongue

Height N/A (Primarily an outdoor plant, not suitable for indoor growing)
Spread N/A (Primarily an outdoor plant, not suitable for indoor growing)
Growth Rate Moderate
Growth Pattern Hound's Tongue grows as a rosette of basal leaves in its first year. In the second year, it sends up an erect flowering stem, typically branching near the top. It is a taprooted plant, which helps it tolerate drought conditions.

Larkspur Delphinium

Height Rarely grown indoors, outdoor height 0.3-1.8 meters
Spread 0.3-0.6 meters
Growth Rate Moderate
Growth Pattern Upright, with tall flower spikes emerging from a basal rosette of foliage.

🌱 Propagation — Comparing Plant Growth

Hound's Tongue

Methods: Seed

Difficulty: Easy

Tips: Sow seeds in the fall or early spring. Cold stratification (exposing seeds to cold temperatures for a period) can improve germination rates. Direct sow into well-drained soil and lightly cover with soil. Keep the soil moist until germination occurs.

Larkspur Delphinium

Methods: Seed, Division

Difficulty: Moderate

Tips: For seeds, cold stratification is often required. Divide established plants in early spring or fall.

✨ Benefits & Features — Comparing Plant Value

Hound's Tongue

The plant's barbed seeds are its most distinctive feature, allowing them to cling to fur and clothing for dispersal. Its toxicity due to pyrrolizidine alkaloids sets it apart from many other common garden plants.

  • ✓ Attracts pollinators
  • ✓ Adds visual interest to a wildflower garden
  • ✓ Drought-tolerant once established
  • ✓ Historically used in traditional medicine
  • ✓ Unique seed dispersal method
  • ⚠️ Toxic to pets

Larkspur Delphinium

Larkspurs are known for their tall, elegant flower spikes and vibrant colors. They are a classic cottage garden flower and a favorite of pollinators. Their toxicity makes them unsuitable for homes with pets or small children.

  • ✓ Attracts pollinators to your garden.
  • ✓ Adds vertical interest and vibrant colors to outdoor spaces.
  • ✓ Provides cut flowers for bouquets.
  • ✓ Can be used to create a classic cottage garden aesthetic.
  • ✓ Offers a sense of accomplishment for experienced gardeners.
  • ⚠️ Toxic to pets

📅 Maintenance Schedule — Plant Care Comparison

Hound's Tongue

Repotting N/A (Not suitable for container growing)
Pruning Remove spent flower stalks to prevent self-seeding if desired. Prune any dead or damaged foliage as needed.
Fertilizing Not generally needed; avoid over-fertilizing. A light application of balanced fertilizer in early spring can be beneficial in nutrient-poor soils.
Seasonal Care In the fall, allow seed heads to dry if you want natural reseeding, or remove them to prevent spread. In winter, the plant may die back to the ground, but it will re-emerge in the spring. No special winter protection is needed in most climates.

Larkspur Delphinium

Repotting Not applicable for indoor growing, but outdoor plants may need division every 3-4 years.
Pruning Deadhead spent flowers to encourage further blooming. Cut back foliage in the fall after flowering.
Fertilizing Balanced fertilizer (10-10-10) applied in spring and early summer at half strength
Seasonal Care In spring, fertilize and provide support for tall varieties. In summer, water regularly and deadhead spent flowers. In fall, cut back foliage after flowering. In winter, provide mulch for protection in colder climates.

🌞 Light Requirements

Hound's Tongue

Full sun to partial shade

Low light tolerant: ❌ No

Larkspur Delphinium

Full sun

Low light tolerant: ❌ No

💧 Watering Needs

Hound's Tongue

Water deeply when the top inch of soil feels dry. Avoid overwatering, as this can lead to root rot. During the first year, water regularly to establish the plant. Once established, it is relatively drought-tolerant. Signs of underwatering include wilting leaves, while overwatering can cause yellowing and mushy stems.

Larkspur Delphinium

Water deeply when the top inch of soil feels dry. Avoid overhead watering to prevent fungal diseases. Overwatering can lead to root rot, indicated by yellowing leaves and wilting. Underwatering results in dry, crispy leaves and stunted growth.

🌡️ Temperature & Humidity

Hound's Tongue

Temperature: 10-25°C

Humidity: 30-50%

Larkspur Delphinium

Temperature: 15-24°C

Humidity: 30-50%

🤔 Which Plant Is Right For You?

Hound's Tongue

Hound's Tongue

Cynoglossum officinale
Care: Expert Time: 15 minutes weekly (primarily for monitoring spread and removing seed heads) Beginner: No

Experienced gardeners in rural settings who understand the risks associated with toxic plants and can manage its spread.

✅ Choose This Plant If...

  • You want a plant with a unique seed dispersal mechanism.
  • You are interested in plants with a historical medicinal background (though not recommended for modern use).
  • You have a large, sunny garden area where it can be contained.
  • You are experienced with managing potentially invasive plants.
  • You want to attract pollinators to your garden.

❌ Skip This Plant If...

  • You have pets or small children who might ingest the plant.
  • You are looking for an indoor plant.
  • You live in an area where it is considered an invasive species.
  • You prefer low-maintenance, worry-free plants.
  • You are a beginner gardener.
📍 Ideal Location: Outdoor garden or meadow with full sun and well-drained soil
🎨 Style: Wildflower, Cottage Garden
🏠 Apartment Friendly: No
⚠️ All parts of the plant, especially the seeds, contain pyrrolizidine alkaloids, which are toxic to dogs, cats, horses, and humans. Symptoms include liver damage, photosensitization, and neurological issues. Ingestion can be fatal in severe cases. Contact a veterinarian or medical professional immediately if ingestion is suspected.
Larkspur Delphinium

Larkspur Delphinium

Delphinium spp.
Care: Expert Time: 30 minutes weekly (weeding, watering, deadheading) Beginner: No

Experienced gardeners looking to add vertical interest and vibrant colors to their outdoor flower beds.

✅ Choose This Plant If...

  • You want tall, vibrant flowers in your garden.
  • You want to attract pollinators to your yard.
  • You have a sunny garden spot that needs a vertical accent.
  • You enjoy the challenge of growing somewhat finicky plants.
  • You appreciate classic cottage garden flowers.

❌ Skip This Plant If...

  • You have pets or small children who might ingest the plant.
  • You lack a sunny outdoor garden space.
  • You are a beginner gardener looking for easy-to-grow plants.
📍 Ideal Location: Outdoor flower beds or borders with full sun exposure
🎨 Style: Cottage, Traditional, English Garden
🏠 Apartment Friendly: No
⚠️ All parts of the plant, especially the seeds, are toxic to dogs, cats, and horses. Symptoms include gastrointestinal upset, weakness, and potentially neurological issues. Contains toxic alkaloids.

🎯 Quick Verdict

Best for Beginners Neither ideal
Pet Friendly Neither - caution
Less Maintenance Similar effort
Apartment Friendly Check space

⚡ Key Differences Between These Plants

☀️

Hound's Tongue needs full sun to partial shade, while Larkspur Delphinium prefers full sun.

💡 Pro Tips For Comparing These Plants

Hound's Tongue Care Tips

Hound's Tongue is primarily an outdoor plant and is not suitable for indoor growing. It requires full sun and well-drained soil. Due to its toxicity, it's crucial to keep it away from pets and children. It is relatively low-maintenance once established, but its toxic nature makes it a less desirable garden plant.

  • Monitor for spread and remove seed heads to prevent unwanted seedlings.
  • Wear gloves when handling the plant to avoid skin irritation.
  • Provide well-drained soil to prevent root rot.
  • Water deeply but infrequently once established.
  • Be aware of its toxicity and keep it away from pets and children.
❄️ Winter: The plant may die back to the ground in winter, especially in colder climates. No special winter protection is needed, as it is relatively cold-hardy.
☀️ Summer: Provide adequate water during dry periods. Monitor for pests and diseases. Remove spent flower stalks to prevent unwanted self-seeding.

Larkspur Delphinium Care Tips

Larkspurs are challenging to grow indoors due to their high light requirements and need for cool temperatures. They are best suited for outdoor gardens. Indoor attempts often result in weak, leggy growth and failure to flower. Proper drainage is crucial.

  • Provide support for tall varieties to prevent them from falling over.
  • Ensure well-draining soil to prevent root rot.
  • Deadhead spent flowers regularly to encourage more blooms.
  • Protect from strong winds that can damage the flower spikes.
  • Monitor for pests and diseases and treat promptly.
❄️ Winter: Cut back foliage after flowering. Provide mulch for protection in colder climates.
☀️ Summer: Water regularly and deadhead spent flowers. Provide support for tall varieties.

⚠️ Common Problems & Solutions — Plant Care Comparison

Hound's Tongue

Common Issues: Spreading, Toxicity, Susceptibility to pests and diseases
Solutions: Control spread by removing seed heads before they mature. | Keep away from pets and children due to toxicity. | Monitor for pests and diseases, and treat accordingly with appropriate insecticides or fungicides.

Larkspur Delphinium

Common Issues: Powdery mildew, Crown rot, Aphids, Spider mites
Solutions: Powdery mildew: Improve air circulation and apply fungicide. Crown rot: Ensure well-draining soil and avoid overwatering. Aphids: Insecticidal soap. Spider mites: Increase humidity and use miticide.

❓ Frequently Asked Questions — Comparing These Plants

Hound's Tongue

What are the light requirements for Hound's Tongue?

Hound’s Tongue prefers partial to full sun, but the ideal amount of sunlight depends on your specific climate. In cooler climates, it can tolerate full sun, but in hotter regions, afternoon shade is crucial to prevent leaf scorch. Aim for at least 6 hours of direct sunlight per day for optimal growth and flowering.

How do I care for Hound's Tongue?

Hound’s Tongue thrives in well-draining soil and prefers partial to full sun, depending on your specific climate. Water thoroughly when the top inch of soil feels dry, but avoid overwatering to prevent root rot. Fertilize sparingly with a balanced, slow-release fertilizer in the spring to promote healthy growth.

How do I propagate Hound's Tongue?

Hound’s Tongue can be propagated through division or seed. Division is best done in the spring or fall. Carefully dig up the plant and separate the root ball into smaller clumps, ensuring each clump has healthy roots and foliage. Replant the divisions in well-draining soil and water thoroughly.

Larkspur Delphinium

What are the light requirements for Larkspur Delphinium?

Larkspur Delphiniums thrive in full sun, needing a minimum of six hours of direct sunlight each day to produce abundant blooms. Insufficient light can lead to leggy growth, weak stems, and reduced flowering. When planting, choose a location that receives morning sun, which helps to dry the foliage and prevent fungal diseases.

How do I care for Larkspur Delphinium?

Larkspur Delphiniums need well-draining soil enriched with organic matter. Plant in a location with full sun, providing at least six hours of direct sunlight daily. Water deeply when the top inch of soil feels dry, but avoid overwatering. Fertilize regularly during the growing season with a balanced fertilizer, switching to a fertilizer higher in phosphorus to promote blooming.

How do I propagate Larkspur Delphinium?

Larkspur Delphiniums can be propagated by division, stem cuttings, or seed. Division is best done in spring or fall by carefully separating the root ball and replanting the divisions. For stem cuttings, take 4-6 inch cuttings from new growth in spring, remove the lower leaves, and plant in a well-draining rooting medium. Keep the cuttings moist and in a humid environment until rooted.

Last updated: May 5, 2026 — Plant care data reviewed and verified by our editorial team.