Larkspur Delphinium vs Perennial Pea Plant Comparison
Compare these two plants side by side — care needs, key differences, and which is right for your home.
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.
Perennial Pea
Lathyrus latifolius
Lathyrus latifolius, commonly known as Perennial Pea, is a climbing perennial vine that can reach lengths of 6 feet or more. It features winged stems and tendrils that allow it to scramble over other plants or structures. The plant produces showy, pea-like flowers in shades of pink, rose, purple, and white during the summer months. While visually appealing, it's primarily an outdoor plant and not suited for indoor cultivation due to its need for full sun and extensive root system. People grow it for its attractive flowers and ability to cover fences or trellises.
Quick Plant Comparison
| Feature | Larkspur Delphinium | Perennial Pea |
|---|---|---|
| Light | Full sun | Full sun (at least 6 hours of direct sunlight daily) |
| Watering | Every 3-7 days, depending on weather and soil drainage | Every 7-10 days, depending on weather conditions |
| Humidity | 30-50% | 30-50% |
| Temperature | 15-24°C | 15-25°C |
| Care Level | Expert | Expert |
| Growth Rate | Moderate | Fast |
| Max Height | Rarely grown indoors, outdoor height 0.3-1.8 meters | N/A (Outdoor plant, not suitable for indoor growing) |
| 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 |
| Beginner Friendly | ❌ No | ❌ No |
| Weekly Maintenance | 30 minutes weekly (weeding, watering, deadheading) | 30 minutes weekly during growing season |
🔬 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. |
Perennial Pea
| Scientific Name | Lathyrus latifolius |
|---|---|
| Family | Fabaceae |
| Native To | Europe |
| Also Known As | Perennial Pea, Everlasting Pea, Broad-leaved Everlasting Pea |
| Leaves | The leaves are alternate, pinnately compound with two leaflets and a terminal tendril. The leaflets are lance-shaped, 5-10 cm long, and have a bluish-green color. |
| Flowers | The flowers are pea-like, about 2-3 cm wide, and come in shades of pink, rose, purple, and white. They are borne in clusters on long stalks during the summer months. It will not flower indoors. |
📏 Size & Growth — Plant Comparison
Larkspur Delphinium
Perennial Pea
🌱 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.
Perennial Pea
Methods: Seed, Division, Root cuttings
Difficulty: Easy
Tips: Soak seeds in warm water for 24 hours before planting to improve germination. Divide established plants in spring or fall. Root cuttings can be taken in late fall or early 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
Perennial Pea
The Perennial Pea is a long-lived perennial vine with showy flowers. Unlike some other pea species, it does not produce edible pods.
- ✓ Attracts pollinators like bees and butterflies.
- ✓ Provides beautiful vertical interest in the garden.
- ✓ Relatively low maintenance once established.
- ✓ Can help to stabilize soil on slopes.
- ✓ Offers a long blooming period throughout the summer.
- ⚠️ Toxic to pets
📅 Maintenance Schedule — Plant Care Comparison
Larkspur Delphinium
Perennial Pea
🌞 Light Requirements
Larkspur Delphinium
Full sun
Low light tolerant: ❌ No
Perennial Pea
Full sun (at least 6 hours of direct sunlight daily)
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.
Perennial Pea
Water deeply when the top inch of soil feels dry. Avoid overwatering, which can lead to root rot. During hot, dry periods, more frequent watering may be necessary. Allow the soil to drain well after watering.
🌡️ Temperature & Humidity
Larkspur Delphinium
Temperature: 15-24°C
Humidity: 30-50%
Perennial Pea
Temperature: 15-25°C
Humidity: 30-50%
🤔 Which Plant Is Right For You?
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.
Perennial Pea
Lathyrus latifoliusGardeners looking for a flowering vine to cover fences, trellises, or walls in a sunny location.
✅ Choose This Plant If...
- You want a fast-growing vine to cover a fence or trellis.
- You have a sunny garden and want to attract pollinators.
- You enjoy the look of pea-like flowers in various colors.
- You are looking for a low-maintenance perennial once established.
- You want a plant that can tolerate a wide range of soil conditions.
❌ Skip This Plant If...
- You have pets or small children who might ingest the plant.
- You have a small garden and are concerned about aggressive spreading.
- You are looking for an indoor plant.
- You don't have a location with full sun.
- You are sensitive to plants that may cause skin irritation.
🎯 Quick Verdict
⚡ Key Differences Between These Plants
Larkspur Delphinium needs full sun, while Perennial Pea prefers full sun (at least 6 hours of direct sunlight daily).
Larkspur Delphinium has moderate growth, while Perennial Pea 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.
Perennial Pea Care Tips
Perennial Pea is an outdoor plant that requires full sun and well-drained soil. It is not suitable for indoor growing due to its light and space requirements. It can be an aggressive spreader, so containment may be necessary. Toxicity to pets is a significant concern.
- Provide a sturdy support structure for the vine to climb.
- Deadhead spent flowers to encourage continued blooming.
- Monitor for signs of powdery mildew and treat promptly.
- Control spread by pruning and removing unwanted seedlings.
- Avoid planting near areas where pets or children have access.
⚠️ Common Problems & Solutions — Plant Care Comparison
Larkspur Delphinium
Perennial Pea
❓ 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.
Perennial Pea
What are the light requirements for Perennial Pea?
Perennial Pea requires at least 6-8 hours of direct sunlight per day to thrive and produce abundant blooms. A south-facing location is ideal, but east or west-facing exposures can also work if they provide sufficient sunlight. In hotter climates, some afternoon shade can be beneficial to prevent scorching of the leaves and flowers. Insufficient light can lead to leggy growth, reduced flowering, and pale foliage. If growing indoors, supplement with grow lights if natural light is limited. Rotate the plant regularly to ensure even light exposure on all sides. Monitor your Perennial Pea closely and adjust its location as needed to ensure it receives adequate sunlight.
How do I care for Perennial Pea?
Perennial Pea thrives in full sun to partial shade and requires well-drained soil. Water regularly, especially during dry periods, but avoid overwatering, which can lead to root rot. Fertilize in spring with a balanced fertilizer to promote healthy growth and abundant blooms. Deadhead spent flowers to encourage continued flowering throughout the season. Provide a sturdy support structure, such as a trellis or fence, for the plant to climb. Prune back in late fall or early spring to control its size and shape. Watch out for common pests like aphids and spider mites, and treat infestations promptly. Mulch around the base of the plant to retain moisture and suppress weeds. Regular monitoring and preventative measures are key to keeping your Perennial Pea healthy and vibrant.
How do I propagate Perennial Pea?
Perennial Pea can be propagated by seed, division, or stem cuttings. For seed propagation, scarify the seeds and soak them in water for 24 hours before planting. Sow seeds indoors in early spring or directly outdoors after the last frost. For division, carefully dig up a mature plant in early spring or late fall and divide the root ball into smaller sections, each with its own set of roots and shoots. Replant the divisions in well-draining soil. For stem cuttings, take 4-6 inch cuttings from healthy stems in late spring or early summer. Remove the lower leaves and dip the cut end in rooting hormone. Plant the cuttings in a well-draining potting mix and keep them moist until they root.
Last updated: May 2, 2026 — Plant care data reviewed and verified by our editorial team.