Franklin Tree vs Larkspur Delphinium Plant Comparison

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

Franklin Tree

Franklin Tree

Franklinia alatamaha

VS
Larkspur Delphinium

Larkspur Delphinium

Delphinium spp.

Franklin Tree

Franklin Tree

Franklinia alatamaha

The Franklin Tree is a deciduous tree or large shrub known for its beautiful camellia-like, fragrant white flowers that bloom in late summer to early fall. It has attractive, glossy green leaves that turn vibrant shades of red and orange in the fall. Sadly, it is extinct in the wild, making it a rare and highly prized ornamental tree. It typically grows to a height of 10-30 feet. People grow it for its stunning floral display, fall color, and historical significance.

Theaceae Southeastern United States (Georgia, along the Altamaha River)
✨ Features: Extinct in the wild, beautiful late-season blooms, stunning fall color.
📖 Read Complete Franklin Tree 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 Franklin Tree Larkspur Delphinium
Light Full sun to partial shade Full sun
Watering 2-3 times per week during the growing season, less frequently in winter, depending on rainfall and soil moisture. Every 3-7 days, depending on weather and soil drainage
Humidity 40-60% 30-50%
Temperature 10-24°C 15-24°C
Care Level Expert Expert
Growth Rate Moderate Moderate
Max Height N/A (Outdoor Tree) Rarely grown indoors, outdoor height 0.3-1.8 meters
Pet Safety ✅ Safe ❌ Toxic To Pets
Soil Well-drained, acidic soil rich in organic matter Well-draining, fertile soil with a slightly acidic to neutral pH (6.0-7.0)
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 30 minutes weekly during growing season. 30 minutes weekly (weeding, watering, deadheading)

🔬 Botanical Information — Comparing These Plants

Franklin Tree

Scientific Name Franklinia alatamaha
Family Theaceae
Native To Southeastern United States (Georgia, along the Altamaha River)
Also Known As Franklin Tree
Leaves The leaves are alternate, simple, oblong to obovate, 3-6 inches long, and have finely serrated margins. They are glossy green in summer and turn brilliant shades of red, orange, and purple in the fall.
Flowers The Franklin Tree produces 3-inch wide, cup-shaped, fragrant white flowers that resemble camellias. The flowers have prominent yellow stamens in the center and bloom in late summer to early fall.

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

Franklin Tree

Height N/A (Outdoor Tree)
Spread N/A (Outdoor Tree)
Growth Rate Moderate
Growth Pattern The Franklin Tree grows as a small to medium-sized deciduous tree or large shrub with an upright, somewhat irregular habit. It typically develops a single trunk or multiple stems.

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

Franklin Tree

Methods: Seed, stem cuttings, root cuttings

Difficulty: Difficult

Tips: Seed propagation requires stratification and can be slow. Stem cuttings are best taken in late spring or early summer. Root cuttings can be taken in late winter.

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

Franklin Tree

The Franklin Tree is unique because it is extinct in the wild and all existing trees are descended from the Bartram's collection. Its late-season blooms and vibrant fall color make it a standout ornamental tree.

  • ✓ Provides late-season blooms for visual interest.
  • ✓ Offers stunning fall foliage color.
  • ✓ Attracts pollinators to the garden.
  • ✓ Adds historical significance to the landscape.
  • ✓ Offers a unique and rare specimen for plant collectors.
  • 🐾 Pet Safe

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

Franklin Tree

Repotting N/A (Outdoor Tree)
Pruning Prune lightly in late winter or early spring to remove dead or damaged branches and maintain shape.
Fertilizing Acid-forming fertilizer in early spring, following package instructions for dosage.
Seasonal Care In spring, fertilize and mulch. In summer, ensure adequate watering. In fall, enjoy the vibrant foliage. In winter, protect from harsh winds and extreme cold.

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

Franklin Tree

Full sun to partial shade

Low light tolerant: ❌ No

Larkspur Delphinium

Full sun

Low light tolerant: ❌ No

💧 Watering Needs

Franklin Tree

Water deeply and regularly, especially during dry periods. Keep the soil consistently moist, but not waterlogged. Overwatering can lead to root rot. Underwatering will cause leaf drop and stress.

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

Franklin Tree

Temperature: 10-24°C

Humidity: 40-60%

Larkspur Delphinium

Temperature: 15-24°C

Humidity: 30-50%

🤔 Which Plant Is Right For You?

Franklin Tree

Franklin Tree

Franklinia alatamaha
Care: Expert Time: 30 minutes weekly during growing season. Beginner: No

Experienced gardeners looking for a unique and historically significant ornamental tree for their landscape.

✅ Choose This Plant If...

  • You want a rare and historically significant tree in your garden.
  • You desire late-season blooms when many other plants have finished flowering.
  • You appreciate vibrant fall foliage.
  • You have acidic, well-drained soil.
  • You are an experienced gardener willing to provide specific care.

❌ Skip This Plant If...

  • You live in a climate with alkaline soil.
  • You are a beginner gardener.
  • You want a low-maintenance plant.
📍 Ideal Location: A sunny or partially shaded spot in the garden with well-drained, acidic soil.
🎨 Style: Traditional, Cottage, Woodland
🏠 Apartment Friendly: No
⚠️ According to available sources, Franklinia alatamaha is not known to be toxic to humans or animals. However, it is always best to supervise pets and children around any plant.
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 Franklin Tree ✓
Less Maintenance Similar effort
Apartment Friendly Check space

⚡ Key Differences Between These Plants

☀️

Franklin Tree needs full sun to partial shade, while Larkspur Delphinium prefers full sun.

💡 Pro Tips For Comparing These Plants

Franklin Tree Care Tips

The Franklin Tree is primarily an outdoor tree and is not suitable for indoor growing. It requires specific soil conditions, consistent moisture, and protection from extreme temperatures. Maintaining proper acidity and drainage is crucial for its survival. Indoor growing is not recommended due to its size and environmental needs.

  • Ensure the soil is consistently moist but not waterlogged.
  • Apply an acid-forming fertilizer in early spring.
  • Mulch around the base of the tree to retain moisture and suppress weeds.
  • Protect from harsh winds and extreme cold in winter.
  • Monitor for pests and diseases and treat promptly.
❄️ Winter: Protect the tree from harsh winds and extreme cold. Mulch around the base to insulate the roots. Avoid pruning in late fall or early winter.
☀️ Summer: Ensure adequate watering during hot, dry periods. Provide some afternoon shade in hotter climates to prevent leaf scorch. Monitor for pests and diseases.

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

Franklin Tree

Common Issues: Root rot, chlorosis (yellowing leaves), susceptibility to pests and diseases
Solutions: Ensure well-drained soil to prevent root rot. Address chlorosis with an acid-forming fertilizer. 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

Franklin Tree

What are the light requirements for Franklin Tree?

Franklin Trees thrive in bright, indirect light. Avoid direct sunlight, especially during the hottest parts of the day, as it can scorch the leaves. An east-facing window is often ideal, providing gentle morning sun. A south- or west-facing window can also work, but be sure to filter the light with a sheer curtain to prevent leaf burn. Insufficient light can lead to leggy growth and reduced flowering.

How do I care for Franklin Tree?

To successfully grow a Franklin Tree indoors, begin with a well-draining potting mix in a pot at least 12 inches in diameter. Place it in a location with bright, indirect light. Water thoroughly when the top inch of soil feels dry, ensuring proper drainage to avoid root rot. Maintain moderate humidity levels, ideally around 50-60%, using a humidifier if necessary.

How do I propagate Franklin Tree?

Franklin Trees can be propagated through stem cuttings and air layering, though both methods can be challenging. For stem cuttings, take a 4-6 inch cutting from new growth in late spring or early summer. Remove the lower leaves and dip the cut end in rooting hormone. Plant the cutting in a well-draining potting mix and keep it consistently moist and humid. Place a plastic bag over the cutting to retain humidity. Rooting can take several weeks to months.

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 15, 2026 — Plant care data reviewed and verified by our editorial team.