Japanese Cedar vs Larkspur Delphinium Plant Comparison
Compare these two plants side by side — care needs, key differences, and which is right for your home.
Japanese Cedar
Cryptomeria japonica
Cryptomeria japonica, commonly known as Japanese Cedar or Sugi, is a large evergreen coniferous tree native to Japan and China. It's characterized by its reddish-brown bark that peels in strips and its spirally arranged, awl-shaped leaves that are typically bluish-green. In its native habitat, it can reach heights of 50-70 meters. While primarily an outdoor tree, some dwarf cultivars are grown in containers. People grow it for its ornamental value, fast growth (in suitable conditions), and use as a privacy screen or windbreak.
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.
Quick Plant Comparison
| Feature | Japanese Cedar | Larkspur Delphinium |
|---|---|---|
| Light | Full sun to partial shade | Full sun |
| Watering | Every 1-2 weeks, depending on weather and soil drainage | Every 3-7 days, depending on weather and soil drainage |
| Humidity | 30-60% | 30-50% |
| Temperature | 10-24°C | 15-24°C |
| Care Level | Expert | Expert |
| Growth Rate | Moderate To Fast | Moderate |
| Max Height | 2-5 meters (in containers, significantly smaller than in the wild) | Rarely grown indoors, outdoor height 0.3-1.8 meters |
| Pet Safety | ❌ Toxic To Pets | ❌ Toxic To Pets |
| Soil | Well-draining, slightly acidic soil | Well-draining, fertile soil with a slightly acidic to neutral pH (6.0-7.0) |
| Beginner Friendly | ❌ No | ❌ No |
| Weekly Maintenance | 30 minutes weekly | 30 minutes weekly (weeding, watering, deadheading) |
🔬 Botanical Information — Comparing These Plants
Japanese Cedar
| Scientific Name | Cryptomeria japonica |
|---|---|
| Family | Cupressaceae |
| Native To | Japan, China |
| Also Known As | Japanese Cedar, Sugi |
| Leaves | The leaves are awl-shaped, spirally arranged, and typically bluish-green. They are about 0.5-1 cm long and have a slightly prickly texture. |
| Flowers | It rarely flowers indoors. Outdoors, it produces small, inconspicuous flowers in spring, followed by small, globular cones. |
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
Japanese Cedar
Larkspur Delphinium
🌱 Propagation — Comparing Plant Growth
Japanese Cedar
Methods: Seed, Cuttings
Difficulty: Moderate
Tips: Take semi-hardwood cuttings in late summer. Use rooting hormone and provide high humidity. Seed propagation requires stratification.
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
Japanese Cedar
Japanese Cedar is a conifer that is not a true cedar, but belongs to the cypress family. Its reddish-brown bark and awl-shaped leaves give it a distinctive appearance. Dwarf cultivars are prized for their compact size and suitability for container growing.
- ✓ Unique aesthetic appeal
- ✓ Can be trained as bonsai
- ✓ Provides a touch of nature indoors
- ✓ Relatively slow-growing in containers
- ✓ Offers a calming presence
- ⚠️ 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
Japanese Cedar
Larkspur Delphinium
🌞 Light Requirements
Japanese Cedar
Full sun to partial shade
Low light tolerant: ❌ No
Larkspur Delphinium
Full sun
Low light tolerant: ❌ No
💧 Watering Needs
Japanese Cedar
Water deeply when the topsoil feels dry to the touch. Avoid overwatering, which can lead to root rot. In containers, ensure proper drainage. During the growing season, water more frequently, and reduce watering in the winter.
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
Japanese Cedar
Temperature: 10-24°C
Humidity: 30-60%
Larkspur Delphinium
Temperature: 15-24°C
Humidity: 30-50%
🤔 Which Plant Is Right For You?
Japanese Cedar
Cryptomeria japonicaExperienced gardeners looking for a unique container plant for a bright, cool location.
✅ Choose This Plant If...
- You appreciate the unique texture and form of conifers
- You have a very bright, cool location for a container plant
- You are an experienced gardener looking for a challenge
- You want a small, slow-growing conifer for bonsai
- You are prepared to provide specific care to maintain its health.
❌ Skip This Plant If...
- You lack a very bright, cool location
- You are a beginner gardener
- You have pets that might ingest the plant
- You want a low-maintenance houseplant.
Larkspur Delphinium
Delphinium spp.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.
🎯 Quick Verdict
⚡ Key Differences Between These Plants
Japanese Cedar needs full sun to partial shade, while Larkspur Delphinium prefers full sun.
Japanese Cedar has moderate to fast growth, while Larkspur Delphinium grows moderate.
💡 Pro Tips For Comparing These Plants
Japanese Cedar Care Tips
Japanese Cedar is primarily an outdoor tree and presents significant challenges when grown indoors. It requires very bright light, well-draining soil, and careful watering to prevent root rot. Maintaining adequate humidity indoors can also be difficult. Only dwarf cultivars are suitable for container growing, and even then, they may not thrive indoors long-term.
- Provide excellent drainage to prevent root rot
- Ensure adequate humidity, especially in dry indoor environments
- Fertilize sparingly with a balanced fertilizer
- Monitor for pests regularly
- Rotate the plant regularly to ensure even growth.
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.
⚠️ Common Problems & Solutions — Plant Care Comparison
Japanese Cedar
Larkspur Delphinium
❓ Frequently Asked Questions — Comparing These Plants
Japanese Cedar
What are the light requirements for Japanese Cedar?
Japanese Cedars require bright, indirect light to thrive indoors. Direct sunlight can scorch their delicate foliage, leading to brown tips and overall stress. A location near an east-facing window is often ideal, providing ample morning light without the harsh afternoon sun. If placed near a south- or west-facing window, use sheer curtains to filter the light. Insufficient light can result in leggy growth and a loss of foliage density. Rotate the plant regularly to ensure all sides receive adequate light exposure. If natural light is limited, consider supplementing with a grow light to maintain healthy growth and vibrant color.
How do I care for Japanese Cedar?
Japanese Cedars thrive indoors with bright, indirect light; avoid direct sunlight, which can scorch the foliage. Water thoroughly when the top inch of soil feels dry, ensuring good drainage to prevent root rot. Maintain high humidity levels through misting or a humidifier, especially during dry months. Use a well-draining potting mix formulated for conifers or evergreens. Fertilize sparingly during the growing season (spring and summer) with a balanced, slow-release fertilizer. Prune regularly to maintain the desired shape and size. Repot every 2-3 years as needed, choosing a slightly larger pot. Provide stable temperatures, avoiding sudden fluctuations and drafts. Rotate the plant regularly to ensure even growth. Monitor for pests like spider mites and treat promptly.
How do I propagate Japanese Cedar?
Japanese Cedars can be propagated through stem cuttings or air layering, though success rates can vary. For stem cuttings, take 4-6 inch cuttings from new growth in spring or early summer. Remove the lower needles and dip the cut end in rooting hormone. Plant the cutting in a well-draining potting mix and keep it moist and humid by covering with a plastic bag or humidity dome. For air layering, make a small incision on a branch, wrap it with moist sphagnum moss, and cover it with plastic wrap. Secure the wrap tightly and keep the moss moist. Once roots have formed, cut the branch below the rooted section and pot it up. Both methods require patience and consistent care.
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 12, 2026 — Plant care data reviewed and verified by our editorial team.