Butterfly-bush
Buddleja davidii · Orange-eyed Butterfly-bush · Orange Eye ButterflybushUSDA | Grow Zone
5-10Outdoors all year in zones 5 to 10. Anywhere colder, keep it as a houseplant. Protect it below 32°F.
- Light
- Full sun, 6-8 hours
- Water
- Every 1-2 weeks
- Humidity
- 40-60%
- Temperature
- 65-75°F (18-24°C)
- Difficulty
- Beginner
- Growth
- Moderate
- Mature size
- 4-10 ft tall, 3-4 ft wide
Buddleja davidii, commonly known as Butterfly-bush, is a stunning perennial that attracts butterflies and hummingbirds. Originating from Asia, it is cherished for its fragrant, colorful blooms and ability to thrive in various garden settings.
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Ideal temperature
65-75°F is where it grows fastest. Below 32°F cold damage starts.
Spacing and harvest
- Mature size
- 4-10 ft tall, 3-4 ft wide
- Plant apart
- 36-48 in
- Frost
- Half hardy: light frost only
Everything it needs
9 essentials at a glance
Watering
Buddleja davidii prefers well-drained soil and should be watered deeply but infrequently.
Water every 1-2 weeks during the growing season, allowing the top inch of soil to dry out between waterings. In hotter months, you may need to increase frequency. Signs of over-watering include yellowing leaves and root rot, while under-watering may cause wilting and leaf drop.
Light
This plant thrives in full sun, requiring at least 6-8 hours of direct sunlight daily.
Ideal placement is in a south or west-facing garden bed or container. While it can tolerate partial shade, reduced flowering may occur, so full sun is recommended for optimal growth.
Soil
Buddleja davidii prefers a well-draining soil mix, ideally sandy or loamy with a pH range of 6.0 to 7.5.
Ensure good drainage to prevent root rot, and consider using a potting mix designed for flowering shrubs if growing in a container.
Humidity
This plant prefers average humidity levels, around 40-60%.
To increase humidity, mist the leaves or place a humidifier nearby. Signs of humidity stress include browning leaf tips and edges, while excessive humidity can lead to fungal issues.
Temperature
Buddleja davidii thrives in temperatures between 65-75°F (18-24°C) and is hardy in USDA zones 5-10.
It can tolerate heat but may struggle in extreme cold, so protect it from frost in colder climates by covering or bringing potted plants indoors.
Fertilizing
Use a balanced fertilizer with an NPK ratio of 10-10-10 or 20-20-20 during the growing season.
Fertilize every 4-6 weeks from spring to early fall. Signs of nutrient deficiency include stunted growth and poor flowering, which can be remedied with appropriate fertilization.
Pruning
Prune Buddleja davidii in late winter or early spring before new growth begins.
Use sharp, clean pruning shears to remove dead or damaged stems, and shape the plant to encourage bushiness. Deadheading spent flowers throughout the blooming season can promote additional flowering.
Repotting
Repot Buddleja davidii every 2-3 years or when the roots outgrow the pot.
Choose a pot that is 1-2 inches larger in diameter. Signs it needs repotting include roots growing out of the drainage holes or stunted growth. When repotting, gently remove the plant from its pot, loosen the roots, and place it in fresh potting mix.
Propagation
Propagation can be achieved through stem cuttings or seeds.
For stem cuttings, take 4-6 inch cuttings in late spring or early summer, remove lower leaves, and place in a moist potting mix. Keep the cuttings in a warm, humid environment until roots develop. For seeds, sow in spring after the last frost, covering lightly with soil.
When it's unhappy
Yellow leaves
Why it happens
Often caused by over-watering or nutrient deficiency.
How to fix it
Adjust watering schedule and consider fertilizing with a balanced fertilizer.
Root rot
Why it happens
Excess moisture in the soil leading to fungal infections.
How to fix it
Ensure proper drainage and reduce watering frequency. Remove affected roots and repot in fresh soil.
Poor flowering
Why it happens
Insufficient sunlight or lack of pruning.
How to fix it
Ensure the plant receives full sun and prune back in early spring to encourage blooming.
Leaf spot
Why it happens
Fungal infections due to high humidity or poor air circulation.
How to fix it
Improve air circulation around the plant and apply a fungicide if necessary.
Pests (aphids, spider mites)
Why it happens
Common pests attracted to the plant, especially in dry conditions.
How to fix it
Regularly inspect the plant and treat infestations with insecticidal soap or neem oil.
Care through the year
Spring
In spring, prune back any dead or damaged stems and fertilize with a balanced fertilizer to promote new growth. Monitor for pests as new growth emerges.
Summer
During summer, ensure consistent watering, especially in hot weather. Deadhead spent flowers to encourage continuous blooming and check for pests regularly.
Fall
In fall, reduce watering as temperatures cool. Consider applying a layer of mulch to protect the roots during winter and prepare for dormancy.
Winter
In winter, protect the plant from frost by covering it or bringing potted plants indoors. Avoid excessive watering during dormancy.
Toxicity & Safety
Buddleja davidii is considered non-toxic to pets and children. However, ingestion of large quantities may cause mild gastrointestinal upset. Always monitor pets around plants to prevent any potential issues.
Good to know
How often should I water my Buddleja davidii?
Water Buddleja davidii every 1-2 weeks, allowing the top inch of soil to dry out between waterings. Adjust frequency based on weather conditions.
Why are my Butterfly-bush leaves turning yellow?
Yellow leaves can indicate over-watering or nutrient deficiency. Check your watering schedule and consider fertilizing if needed.
When is the best time to prune Buddleja davidii?
The best time to prune is in late winter or early spring before new growth begins. This encourages bushiness and more blooms.
What type of soil is best for Butterfly-bush?
Buddleja davidii prefers well-draining sandy or loamy soil with a pH of 6.0 to 7.5. Good drainage is essential to prevent root rot.
Can I grow Buddleja davidii in a pot?
Yes, Buddleja davidii can be grown in pots. Ensure the container has drainage holes and use a suitable potting mix for flowering shrubs.
How can I encourage more blooms on my Butterfly-bush?
To encourage more blooms, ensure the plant receives full sun, deadhead spent flowers regularly, and prune in early spring.
Is Buddleja davidii toxic to pets?
Buddleja davidii is considered non-toxic to pets and children, but ingestion of large quantities may cause mild gastrointestinal upset.
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