Butterfly Bush vs Delphinium Plant Comparison

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

Butterfly Bush

Butterfly Bush

Buddleja davidii

VS
Delphinium

Delphinium

Delphinium spp.

Butterfly Bush

Butterfly Bush

Buddleja davidii

Buddleja davidii, commonly known as Butterfly Bush, is a deciduous shrub known for its fragrant, nectar-rich flowers that attract butterflies and other pollinators. It typically grows to a height of 6-12 feet and a spread of 4-15 feet in its natural outdoor environment. It features arching branches and lance-shaped leaves. While highly desirable for its beauty and wildlife attraction, it is primarily an outdoor plant and presents significant challenges when grown indoors due to its need for intense sunlight and large size. People grow it for its beautiful flowers and to attract butterflies.

Scrophulariaceae China, Japan
✨ Features: Attracts butterflies and other pollinators.
📖 Read Complete Butterfly Bush Guide
Delphinium

Delphinium

Delphinium spp.

Delphiniums are perennial herbaceous plants known for their tall, striking flower spikes. They typically grow outdoors and are prized for their vibrant blue, purple, pink, and white flowers. The plant has deeply lobed leaves and a robust stem that supports the flower spike. They are not suited for indoor growing due to their high light requirements and size. People grow them in gardens for their aesthetic appeal and to attract pollinators.

Ranunculaceae Northern Hemisphere, including Europe, Asia, and North America
✨ Features: Attracts pollinators (bees and butterflies)
📖 Read Complete Delphinium Guide

Quick Plant Comparison

Feature Butterfly Bush Delphinium
Light Full sun (at least 6-8 hours of direct sunlight daily) Full sun (at least 6 hours of direct sunlight per day)
Watering Outdoors: Once or twice a week during the growing season, less frequently in winter. Indoors (not recommended): Extremely difficult to maintain proper moisture levels. 2-3 times per week, depending on weather and soil drainage
Humidity 30-50% 40-60%
Temperature 15-27°C 15-24°C
Care Level Expert Expert
Growth Rate Fast Moderate
Max Height Indoors: Unlikely to thrive and reach full size; potentially 1-3 feet in a very large container with ideal conditions. Outdoors: 6-12 feet. Not typically grown indoors; outdoors: 0.6-1.8 meters
Pet Safety ❌ Toxic To Pets ❌ Toxic To Pets
Soil Well-draining soil; a mix of garden soil, sand, and compost is suitable. Well-draining, fertile soil rich in organic matter
Beginner Friendly ❌ No ❌ No
Weekly Maintenance 30 minutes weekly (including watering, pruning, and pest control) 30 minutes weekly (weeding, watering, deadheading)

🔬 Botanical Information — Comparing These Plants

Butterfly Bush

Scientific Name Buddleja davidii
Family Scrophulariaceae
Native To China, Japan
Also Known As Butterfly Bush, Summer Lilac
Leaves The leaves are lance-shaped, opposite, and typically 4-10 inches long. They are usually green or grayish-green and have a slightly rough texture.
Flowers Butterfly Bush produces long, cone-shaped flower clusters (panicles) at the ends of its branches. The flowers come in a variety of colors, including purple, pink, white, and yellow. Flowering occurs primarily in summer and fall. It is highly unlikely to flower indoors.

Delphinium

Scientific Name Delphinium spp.
Family Ranunculaceae
Native To Northern Hemisphere, including Europe, Asia, and North America
Also Known As Larkspur, Delphinium
Leaves The leaves are deeply lobed and palmate, with a coarse texture. They are typically medium to dark green in color and arranged alternately along the stem.
Flowers Delphiniums rarely, if ever, flower indoors. Outdoors, they produce tall, dense spikes of flowers in shades of blue, purple, pink, and white. The flowers have a distinctive spurred shape.

📏 Size & Growth — Plant Comparison

Butterfly Bush

Height Indoors: Unlikely to thrive and reach full size; potentially 1-3 feet in a very large container with ideal conditions. Outdoors: 6-12 feet.
Spread Indoors: Limited by container size; potentially 1-3 feet. Outdoors: 4-15 feet.
Growth Rate Fast
Growth Pattern Butterfly Bush grows as a deciduous shrub with arching branches. It can become quite large if not pruned regularly, and its growth is vigorous, especially in full sun.

Delphinium

Height Not typically grown indoors; outdoors: 0.6-1.8 meters
Spread Outdoors: 0.3-0.6 meters
Growth Rate Moderate
Growth Pattern Upright, with tall, sturdy stems that support the flower spikes. The plant forms a basal rosette of leaves from which the flowering stems emerge.

🌱 Propagation — Comparing Plant Growth

Butterfly Bush

Methods: Stem cuttings, Seed

Difficulty: Easy

Tips: Take softwood cuttings in spring or hardwood cuttings in late fall. Root in well-draining soil.

Delphinium

Methods: Seed, Division, Stem cuttings

Difficulty: Moderate

Tips: Sow seeds in early spring or fall. Divide established plants in spring or fall. Take stem cuttings in late spring.

✨ Benefits & Features — Comparing Plant Value

Butterfly Bush

Butterfly Bush is known for its ability to attract a wide variety of butterflies and other pollinators with its fragrant, nectar-rich flowers. Its fast growth rate and adaptability to various soil conditions make it a popular choice for gardeners.

  • ✓ Attracts butterflies and other pollinators
  • ✓ Provides beautiful, fragrant flowers
  • ✓ Adds visual interest to the garden
  • ✓ Supports local ecosystems
  • ✓ Can be used for cut flowers
  • ⚠️ Toxic to pets

Delphinium

Delphiniums are known for their towering flower spikes, which can reach impressive heights. The intense blue color of some varieties is particularly striking and relatively rare in the plant world.

  • ✓ Attracts pollinators to the garden
  • ✓ Adds vibrant color and height to flower beds
  • ✓ Provides cut flowers for arrangements
  • ✓ Enhances the aesthetic appeal of outdoor spaces
  • ✓ Can be used in traditional medicine (with caution and expert knowledge)
  • ⚠️ Toxic to pets

📅 Maintenance Schedule — Plant Care Comparison

Butterfly Bush

Repotting Not applicable for indoor growing due to unsuitability. If attempted, repot annually in spring into a larger container.
Pruning Prune hard in early spring to remove dead or weak wood and to shape the plant. Deadhead spent flowers to encourage continued blooming.
Fertilizing Balanced fertilizer (10-10-10) in spring and early summer. Dilute to half strength.
Seasonal Care Prune hard in early spring to encourage new growth and flowering. Reduce watering in winter. Provide winter protection in colder climates.

Delphinium

Repotting Not applicable for indoor growing; for outdoor plants, division may be needed every 3-4 years.
Pruning Deadhead spent flowers to encourage further blooming. Cut back foliage in the fall.
Fertilizing Balanced fertilizer (10-10-10) applied in spring and early summer at half strength
Seasonal Care Spring: Fertilize and provide support for tall flower spikes. Summer: Water regularly and deadhead spent flowers. Fall: Cut back foliage after flowering. Winter: Provide mulch for protection in colder climates.

🌞 Light Requirements

Butterfly Bush

Full sun (at least 6-8 hours of direct sunlight daily)

Low light tolerant: ❌ No

Delphinium

Full sun (at least 6 hours of direct sunlight per day)

Low light tolerant: ❌ No

💧 Watering Needs

Butterfly Bush

Water deeply when the top inch of soil is dry. Avoid overwatering, which can lead to root rot. Signs of underwatering include wilting leaves and dry soil. Signs of overwatering include yellowing leaves and soggy soil.

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 a mushy stem. Underwatering results in wilting and dry, crispy leaves.

🌡️ Temperature & Humidity

Butterfly Bush

Temperature: 15-27°C

Humidity: 30-50%

Delphinium

Temperature: 15-24°C

Humidity: 40-60%

🤔 Which Plant Is Right For You?

Butterfly Bush

Butterfly Bush

Buddleja davidii
Care: Expert Time: 30 minutes weekly (including watering, pruning, and pest control) Beginner: No

Gardeners with outdoor space who want to attract butterflies and other pollinators.

✅ Choose This Plant If...

  • You want to attract butterflies and other pollinators to your garden.
  • You have a sunny outdoor space.
  • You enjoy fragrant flowers.
  • You are willing to prune regularly.
  • You want a fast-growing shrub.

❌ Skip This Plant If...

  • You have limited outdoor space.
  • You are looking for an easy indoor plant.
  • You have pets that might ingest the plant.
  • You live in an area where it is considered invasive.
📍 Ideal Location: Outdoor garden or sunny patio.
🎨 Style: Cottage, Naturalistic, Wildlife Garden
🏠 Apartment Friendly: No
⚠️ According to the ASPCA, Butterfly Bush is toxic to dogs, cats, and horses. Symptoms include vomiting and diarrhea. All parts of the plant are considered toxic.
Delphinium

Delphinium

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

Gardeners looking to add height and vibrant color to their flower beds.

✅ Choose This Plant If...

  • You want a tall, dramatic flower for your garden.
  • You want to attract pollinators to your yard.
  • You have a sunny garden spot with well-draining soil.
  • You enjoy the classic cottage garden aesthetic.
  • You are an experienced gardener looking for a rewarding challenge.

❌ Skip This Plant If...

  • You have limited sunlight in your home.
  • You have pets or small children who might ingest the plant.
  • You are a beginner gardener looking for an easy-to-grow plant.
📍 Ideal Location: Outdoor garden bed with full sun exposure
🎨 Style: Cottage, Traditional, English Garden
🏠 Apartment Friendly: No
⚠️ Toxic to dogs, cats, and horses. All parts of the plant, especially the seeds, contain toxic alkaloids. Symptoms include gastrointestinal upset, weakness, and potentially cardiac problems.

🎯 Quick Verdict

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

⚡ Key Differences Between These Plants

☀️

Butterfly Bush needs full sun (at least 6-8 hours of direct sunlight daily), while Delphinium prefers full sun (at least 6 hours of direct sunlight per day).

📈

Butterfly Bush has fast growth, while Delphinium grows moderate.

💡 Pro Tips For Comparing These Plants

Butterfly Bush Care Tips

Butterfly Bush is primarily an outdoor plant and is very difficult to grow indoors due to its high light requirements and potential size. It needs full sun, well-draining soil, and regular pruning. Indoor cultivation is not recommended unless you can provide intense supplemental lighting and a very large container.

  • Prune in early spring to encourage new growth.
  • Deadhead spent flowers to prolong blooming.
  • Provide well-draining soil to prevent root rot.
  • Fertilize in spring and early summer.
  • Monitor for pests and diseases regularly.
❄️ Winter: In colder climates, provide winter protection by mulching around the base of the plant. Reduce watering during dormancy. Pruning should be done in early spring, not in the fall or winter.
☀️ Summer: Provide regular watering during hot, dry periods. Deadhead spent flowers to encourage continued blooming. Monitor for pests and diseases.

Delphinium Care Tips

Delphiniums are primarily outdoor plants and are very challenging to grow indoors due to their high light requirements and need for specific temperature and humidity conditions. They require full sun, well-draining soil, and regular fertilization. Indoor cultivation is not recommended.

  • Provide support for tall flower spikes to prevent them from bending or breaking.
  • Deadhead spent flowers regularly to encourage more blooms.
  • Protect from slugs and snails, especially young plants.
  • Ensure good drainage to prevent root rot.
  • Apply a layer of mulch around the base of the plant to retain moisture and suppress weeds.
❄️ Winter: Cut back foliage after flowering. Apply a layer of mulch around the base of the plant to protect the crown from freezing temperatures. In colder climates, consider providing additional winter protection.
☀️ Summer: Water regularly during hot, dry periods. Deadhead spent flowers to encourage more blooms. Provide support for tall flower spikes to prevent them from bending or breaking in strong winds.

⚠️ Common Problems & Solutions — Plant Care Comparison

Butterfly Bush

Common Issues: Spider mites, Aphids, Root rot, Powdery mildew
Solutions: Spider mites/Aphids: Insecticidal soap or neem oil. Root rot: Improve drainage, reduce watering. Powdery mildew: Fungicide, improve air circulation.

Delphinium

Common Issues: Powdery mildew, Crown rot, Aphids, Slugs/Snails
Solutions: Powdery mildew: Improve air circulation and apply fungicide. Crown rot: Ensure good drainage and avoid overwatering. Aphids: Spray with insecticidal soap. Slugs/Snails: Use slug bait or handpick.

❓ Frequently Asked Questions — Comparing These Plants

Butterfly Bush

What are the light requirements for Butterfly Bush?

Butterfly Bush requires a minimum of 6 hours of direct sunlight per day to thrive and produce abundant blooms. Insufficient sunlight can lead to leggy growth, reduced flowering, and pale foliage. Choose a planting location that receives full sun throughout the day. In hotter climates, some afternoon shade may be beneficial to prevent scorching of the leaves.

How do I care for Butterfly Bush?

Butterfly Bush thrives in full sun, requiring at least 6 hours of direct sunlight daily for optimal blooming. Plant in well-draining soil with a slightly acidic to neutral pH. Water deeply but infrequently, allowing the soil to dry out slightly between waterings to prevent root rot. Fertilize in early spring with a balanced fertilizer to promote healthy growth and abundant flowers.

How do I propagate Butterfly Bush?

Butterfly Bush can be propagated through stem cuttings, division, and, less commonly, from seed. For stem cuttings, take 4-6 inch cuttings from new growth 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 roots develop, usually within a few weeks.

Delphinium

What are the light requirements for Delphinium?

Delphiniums are sun-loving plants and require at least six hours of direct sunlight daily to flourish. Insufficient light can lead to weak stems, poor flowering, and increased susceptibility to diseases. In hotter climates, some afternoon shade can be beneficial to prevent scorching. When selecting a location, consider the sun’s path and ensure the plants receive ample morning sun. Delphiniums grown in partial shade may still survive, but their blooms will be significantly diminished. If growing indoors, supplement with grow lights to provide the necessary intensity and duration of light. Rotate the plant regularly to ensure even light exposure.

How do I care for Delphinium?

Delphiniums require specific care to thrive. Plant in well-draining soil enriched with organic matter. Full sun (at least 6 hours daily) is crucial for optimal blooming. Water deeply but infrequently, allowing the soil to dry slightly between waterings. Fertilize regularly during the growing season with a balanced fertilizer, switching to a high-phosphorus fertilizer as buds develop to promote abundant blooms. Stake tall varieties to prevent them from collapsing under the weight of their flowers or in windy conditions. Deadhead spent blooms to encourage reblooming. Protect from slugs and snails, which can damage young plants. Provide adequate air circulation to prevent fungal diseases. Mulch around the base of the plant to retain moisture and suppress weeds.

How do I propagate Delphinium?

Delphiniums can be propagated through division, stem cuttings, and seeds. Division involves separating mature clumps in early spring or fall. Carefully dig up the plant and divide the root ball into sections, ensuring each section has healthy roots and shoots. Stem cuttings can be taken in spring. Select healthy, non-flowering stems and cut them into 4-6 inch sections. 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. Seeds can be sown indoors in late winter or early spring. Sow seeds thinly in a seed starting mix and keep them moist and warm. Germination typically takes 2-3 weeks.

Last updated: April 26, 2026 — Plant care data reviewed and verified by our editorial team.