Larkspur Delphinium vs Obedient Plant Plant Comparison

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

Larkspur Delphinium

Larkspur Delphinium

Delphinium spp.

VS
Obedient Plant

Obedient Plant

Physostegia virginiana

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
Obedient Plant

Obedient Plant

Physostegia virginiana

Physostegia virginiana, commonly known as Obedient Plant, is a herbaceous perennial native to North America. It's characterized by its upright growth habit and lance-shaped, toothed leaves. The plant produces spikes of tubular flowers in shades of pink, lavender, or white during late summer and early fall. It gets its name from the fact that if you gently bend the flowers on the stem, they will stay in the position you put them, hence 'obedient'. Primarily an outdoor plant, it's grown in gardens for its late-season blooms and attractiveness to pollinators. Indoor cultivation is challenging due to its high light and space requirements.

Lamiaceae Eastern and Central North America
✨ Features: Attracts butterflies and hummingbirds, unique flower positioning.
📖 Read Complete Obedient Plant Guide

Quick Plant Comparison

Feature Larkspur Delphinium Obedient Plant
Light Full sun Full sun to partial shade. Requires at least 6 hours of direct sunlight daily for optimal growth and flowering.
Watering Every 3-7 days, depending on weather and soil drainage Every 3-7 days outdoors, less frequently if in partial shade or cooler conditions. Indoor cultivation is not recommended.
Humidity 30-50% 30-50%
Temperature 15-24°C 15-27°C
Care Level Expert Expert
Growth Rate Moderate Fast
Max Height Rarely grown indoors, outdoor height 0.3-1.8 meters Outdoor: 60-120 cm. Indoor: Not recommended, but if attempted, expect significantly stunted growth.
Pet Safety ❌ Toxic To Pets ❌ Toxic To Pets
Soil Well-draining, fertile soil with a slightly acidic to neutral pH (6.0-7.0) Well-drained soil, loamy or sandy soil is preferred. Tolerates a range of soil pH levels.
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 30 minutes weekly (weeding, watering, deadheading) 15 minutes weekly (outdoor)

🔬 Botanical Information — Comparing These Plants

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.

Obedient Plant

Scientific Name Physostegia virginiana
Family Lamiaceae
Native To Eastern and Central North America
Also Known As Obedient Plant, False Dragonhead
Leaves Lance-shaped, toothed leaves that are typically green. They are arranged oppositely along the stem and have a slightly rough texture.
Flowers Flowers are tubular and arranged in spikes. They come in shades of pink, lavender, or white. Flowering occurs in late summer and early fall. Rarely flowers indoors.

📏 Size & Growth — Plant Comparison

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.

Obedient Plant

Height Outdoor: 60-120 cm. Indoor: Not recommended, but if attempted, expect significantly stunted growth.
Spread 30-60 cm. Spreads aggressively via rhizomes.
Growth Rate Fast
Growth Pattern Upright, clump-forming perennial that spreads aggressively via rhizomes. It can form dense colonies if not contained.

🌱 Propagation — Comparing Plant Growth

Larkspur Delphinium

Methods: Seed, Division

Difficulty: Moderate

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

Obedient Plant

Methods: Division, Seed, Stem cuttings

Difficulty: Easy

Tips: Division is best done in spring or fall. For stem cuttings, take cuttings in late spring or early summer and root in water or moist soil. Seeds can be sown directly in the garden in fall or stratified and sown in spring.

✨ Benefits & Features — Comparing Plant Value

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

Obedient Plant

The Obedient Plant is known for its unique flower positioning; the flowers stay in place when gently moved. It's also a late-season bloomer, providing color when many other perennials are finished flowering.

  • ✓ Attracts pollinators to the garden
  • ✓ Provides late-season color
  • ✓ Easy to propagate
  • ✓ Low maintenance once established
  • ✓ Adds a unique touch to floral arrangements
  • ⚠️ Toxic to pets

📅 Maintenance Schedule — Plant Care Comparison

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.

Obedient Plant

Repotting Not recommended for indoor growing. If attempted, repot annually in spring to control rhizomatous spread.
Pruning Cut back spent flower stalks to encourage reblooming. Prune aggressively in spring to control size and shape.
Fertilizing Balanced fertilizer (10-10-10) in spring as new growth emerges. Avoid over-fertilizing, which can lead to leggy growth.
Seasonal Care Spring: Divide if needed, fertilize. Summer: Monitor for pests and diseases, water regularly. Fall: Cut back spent flower stalks, divide if needed. Winter: Dormant, minimal watering.

🌞 Light Requirements

Larkspur Delphinium

Full sun

Low light tolerant: ❌ No

Obedient Plant

Full sun to partial shade. Requires at least 6 hours of direct sunlight daily for optimal growth and flowering.

Low light tolerant: ❌ No

💧 Watering Needs

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.

Obedient Plant

Water deeply when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. In containers, ensure proper drainage. Signs of underwatering include wilting leaves, while overwatering can manifest as yellowing leaves and a soggy soil.

🌡️ Temperature & Humidity

Larkspur Delphinium

Temperature: 15-24°C

Humidity: 30-50%

Obedient Plant

Temperature: 15-27°C

Humidity: 30-50%

🤔 Which Plant Is Right For You?

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.
Obedient Plant

Obedient Plant

Physostegia virginiana
Care: Expert Time: 15 minutes weekly (outdoor) Beginner: No

Gardeners looking for a late-season blooming perennial that attracts pollinators.

✅ Choose This Plant If...

  • You want a late-season bloomer that attracts pollinators.
  • You enjoy unique flower arrangements and the 'obedient' nature of the blooms.
  • You have a sunny garden space and want a low-maintenance perennial.
  • You want to attract butterflies and hummingbirds to your garden.
  • You are looking for a plant that is easy to propagate.

❌ Skip This Plant If...

  • You have limited sunlight indoors.
  • You don't want a plant that spreads aggressively.
  • You have pets that may ingest the plant.
📍 Ideal Location: Outdoor garden, sunny border, meadow garden
🎨 Style: Cottage, Naturalistic, Traditional
🏠 Apartment Friendly: No
⚠️ According to the ASPCA, Obedient Plant is toxic to dogs, cats, and horses. The toxic principle is unknown. Symptoms include gastrointestinal upset (vomiting, diarrhea), and dermatitis.

🎯 Quick Verdict

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

⚡ Key Differences Between These Plants

📈

Larkspur Delphinium has moderate growth, while Obedient Plant grows fast.

💡 Pro Tips For Comparing These Plants

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.

Obedient Plant Care Tips

Obedient Plant is primarily an outdoor plant and requires full sun and well-drained soil. Indoor cultivation is challenging due to its high light requirements and aggressive spreading habit. It can quickly outgrow containers and may not flower properly indoors. Requires careful monitoring of water and fertilizer.

  • Plant in well-drained soil to prevent root rot.
  • Provide full sun for optimal flowering.
  • Divide every few years to control spread and rejuvenate the plant.
  • Deadhead spent flowers to encourage more blooms.
  • Monitor for powdery mildew and rust, especially in humid conditions.
❄️ Winter: Cut back dead foliage in late fall or early spring. Mulch around the base of the plant to protect the roots in colder climates. Minimal watering is needed during dormancy.
☀️ Summer: Water regularly during dry spells. Monitor for pests and diseases. Deadhead spent flowers to encourage more blooms. Provide support if the plant becomes leggy or top-heavy.

⚠️ Common Problems & Solutions — Plant Care Comparison

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.

Obedient Plant

Common Issues: Powdery mildew, Rust, Aggressive spreading, Leggy growth (if not enough light)
Solutions: Powdery mildew: Improve air circulation and apply fungicide. Rust: Remove infected leaves and apply fungicide. Aggressive spreading: Plant in containers or use barriers to contain rhizomes. Leggy growth: Provide more sunlight and prune back to encourage bushier growth.

❓ Frequently Asked Questions — Comparing These Plants

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.

Obedient Plant

What are the light requirements for Obedient Plant?

Obedient Plant thrives best in full sun, requiring at least 6 hours of direct sunlight per day to produce abundant blooms and maintain strong, upright growth. In hotter climates, some afternoon shade can be beneficial to prevent leaf scorch. Insufficient sunlight can lead to leggy growth, reduced flowering, and weaker stems. When grown indoors, place Obedient Plant near a sunny window, such as a south-facing or west-facing exposure. Rotate the plant regularly to ensure even light exposure on all sides. Supplemental lighting may be necessary during winter months or in areas with limited natural light.

How do I care for Obedient Plant?

Obedient Plant thrives in full sun to partial shade and prefers moist, well-drained soil. Water regularly, especially during dry periods, but avoid overwatering to prevent root rot. Fertilize in early spring with a balanced fertilizer to promote healthy growth and abundant blooms. Deadhead spent flowers to encourage further blooming. Be aware that Obedient Plant can be aggressive; consider planting it in containers or using barriers to control its spread. Prune back stems after flowering to maintain shape and prevent excessive self-seeding. Monitor for pests like aphids and spider mites, and treat as needed. Provide adequate air circulation to prevent fungal diseases.

How do I propagate Obedient Plant?

Obedient Plant can be easily propagated through division, stem cuttings, or seeds. Division is best done in early spring or fall by separating the rhizomes and replanting them. For stem cuttings, take 4-6 inch cuttings from healthy stems in late spring or early summer. Remove the lower leaves and plant the cuttings in moist potting mix. Keep the cuttings humid by covering them with a plastic bag or dome. Seeds can be sown directly in the garden in fall or started indoors in early spring. Keep the soil moist until germination.

Last updated: May 1, 2026 — Plant care data reviewed and verified by our editorial team.