Butterfly Bush (Buddleja Davidii ‘Ellen’s Blue’)

Plant: Table of Contents

Butterfly Bush (Buddleja davidii ‘Ellen’s Blue’) – A Complete Guide

The butterfly bush (Buddleja davidii ‘Ellen’s Blue’) is a popular flowering shrub known for its ability to attract butterflies and other pollinators to the garden. This versatile plant offers a range of benefits, from its vibrant blooms and pleasant fragrance to its low-maintenance nature. In this comprehensive guide, we’ll explore the culture, uses, care requirements, maintenance, and other essential aspects of cultivating the butterfly bush. Whether you’re a seasoned gardener or just getting started with your green thumb, this guide will provide you with the knowledge and insights needed to successfully grow and enjoy this beautiful plant.

What is the Butterfly Bush (Buddleja davidii ‘Ellen’s Blue’)?

The butterfly bush, scientifically known as Buddleja davidii ‘Ellen’s Blue’, is a deciduous shrub that belongs to the family Scrophulariaceae. This plant is native to China and has become widely popular in gardens and landscapes around the world due to its stunning flowers and its ability to attract butterflies and other pollinators.

The ‘Ellen’s Blue’ cultivar is particularly prized for its striking blue-purple flowers, which add a vibrant splash of color to any garden. The plant typically grows 4 to 10 feet tall and 5 to 10 feet wide, making it a substantial presence in the garden landscape.

Butterfly bushes have a fast growth rate, and their arching, branching habit gives them an attractive and natural appearance, making them excellent choices for borders, hedges, or as standalone specimens.

Key Takeaways – Butterfly Bush (Buddleja davidii ‘Ellen’s Blue’)

Before we delve into the specifics of cultivating the butterfly bush, let’s highlight the key takeaways that make this plant a desirable addition to any garden or landscape:

  • Attracts butterflies and other pollinators with its abundant nectar-rich flowers
  • ‘Ellen’s Blue’ variety features beautiful blue-purple flowers
  • Fast-growing, low-maintenance shrub ideal for various landscape uses
  • Drought-tolerant once established
  • Pleasantly fragrant flowers make it a sensory delight in the garden
  • Pruning is necessary to promote healthy growth and abundant blooms

Now that we understand the allure of the butterfly bush, let’s explore the essential aspects of successfully growing and caring for this beloved plant.



The butterfly bush offers a range of uses in garden and landscape settings, owing to its beautiful blooms and ability to attract pollinators. Some of its common uses include:

  • Borders and hedges: The dense and arching growth habit of the butterfly bush makes it an excellent choice for creating borders and hedges, adding a splash of color and attracting butterflies along the landscape edges.
  • Pollinator gardens: As a top choice for attracting butterflies, hummingbirds, and bees, butterfly bushes are often used in pollinator gardens or mixed plantings designed to support local pollinator populations.
  • Decorative specimen: When in bloom, the ‘Ellen’s Blue’ cultivar can serve as a stunning stand-alone specimen in the garden, drawing attention with its vibrant flower clusters.


Proper watering is essential for the health and vitality of butterfly bushes, especially during their establishment phase. However, once established, these resilient shrubs are fairly drought-tolerant and can thrive with minimal watering in most climates.

When watering the butterfly bush, aim to provide deep, thorough watering sessions rather than frequent shallow watering. This encourages the development of a robust root system and helps the plant withstand periods of drought more effectively. Avoid overwatering, as this can lead to root rot and other moisture-related issues.


Butterfly bushes thrive in full sun conditions, meaning they require at least 6 to 8 hours of direct sunlight per day to reach their full potential. Plant the ‘Ellen’s Blue’ cultivar in a location that receives ample sunlight to ensure vigorous growth and abundant flowering.

In areas with scorching afternoon sun, consider providing some light afternoon shade to protect the plant from excessive heat stress. However, be mindful not to obstruct the sunlight too much, as this can lead to diminished flowering and overall vigor.


Feeding your butterfly bushes with a balanced fertilizer can help promote healthy growth and prolific blooming. Opt for a slow-release granular fertilizer formulated for flowering shrubs, applying it in early spring as new growth begins to emerge. Follow the manufacturer’s instructions for application rates, as over-fertilizing can lead to excessive vegetative growth at the expense of flowers.

In addition to a balanced fertilizer, incorporating organic matter into the soil during planting can provide an initial nutrient boost and improve the soil’s overall fertility.


Butterfly bushes are adaptable to a wide range of soil types, but they perform best in well-draining soil with a slightly acidic to neutral pH level. Amending heavy clay soils with organic matter such as compost or peat moss can improve drainage and create a more hospitable growing environment for the plant.

When planting the ‘Ellen’s Blue’ cultivar, ensure the soil is loose and well-aerated to support healthy root development. Avoid waterlogged or compacted soil, as this can lead to root suffocation and poor growth.


Pruning plays a crucial role in maintaining the health and vigor of butterfly bushes, as well as promoting abundant flowering. Regular pruning helps to remove spent flower clusters, shape the plant, and stimulate the growth of new shoots.

Pruning Timeline

  • Spring: In early spring, before new growth appears, prune the plant back to about 12 to 18 inches above the ground. This rejuvenation pruning encourages vigorous new growth and results in larger, more abundant flowers during the growing season.

  • Deadheading: Throughout the summer, deadhead the fading flower clusters to prolong the flowering period and prevent the plant from investing energy into seed production. Simply trim the spent flower clusters back to a set of healthy leaves or buds to encourage new growth.

  • Fall: As the growing season comes to a close, consider performing a light pruning to shape the plant and remove any damaged or crossing branches. However, avoid heavy pruning in the fall, as this can stimulate new growth that may be vulnerable to winter frost damage.

Pruning Techniques

When pruning the butterfly bush, use sharp, clean pruning shears to make clean cuts and minimize the risk of disease transmission. Cut the stems at a 45-degree angle just above a set of healthy buds to encourage outward growth and prevent dieback.

As you prune, step back periodically to assess the plant’s overall shape and make adjustments as needed to maintain a balanced and attractive form.


Butterfly bushes can be propagated through several methods, including softwood cuttings, hardwood cuttings, and division. Here’s a brief overview of each propagation technique:

Softwood Cuttings

Softwood cuttings, taken from the tender new growth in late spring to early summer, can be rooted to create new butterfly bush plants. Select healthy, non-flowering shoots and trim them to 4 to 6 inches in length, making the cut just below a node. Remove the lower leaves to expose the nodes and dip the cut end in a rooting hormone. Plant the cuttings in a well-draining rooting medium and provide bottom heat and consistent moisture to encourage root development.

Hardwood Cuttings

In late fall or winter, take hardwood cuttings from the plant’s mature woody growth for propagation. Select pencil-thick, non-flowering shoots and trim them to 6 to 8 inches in length, making a clean cut just below a node. Dip the cut ends in rooting hormone and plant the cuttings in a well-draining medium, keeping them in a sheltered location outdoors until they establish roots.


Mature butterfly bushes can be divided to create multiple plants and rejuvenate older specimens. Dig up the plant in early spring, dividing the root ball into smaller sections using a sharp spade or knife. Each division should have a portion of the root system and several shoots. Replant the divisions in prepared soil, water them thoroughly, and provide ongoing care as they establish in their new location.

Container Popularity

The butterfly bush is a popular choice for container gardening, and the ‘Ellen’s Blue’ cultivar, with its attractive blue-purple flowers, makes a stunning addition to patio, balcony, or deck settings. When grown in containers, butterfly bushes offer the flexibility to be moved around to showcase their blooms or to provide a focal point in outdoor living spaces.

In addition to aesthetic appeal, container-grown butterfly bushes can still attract butterflies and other pollinators, making them a versatile option for urban and small-space gardens. Select a large, sturdy container with adequate drainage holes and use a well-draining potting mix to ensure the plant’s roots have ample aeration.

Place the container in a sunny location and provide regular watering to keep the soil evenly moist, especially during hot and dry periods. As with in-ground plantings, container-grown butterfly bushes benefit from periodic feeding with a balanced fertilizer to support healthy growth and flowering.

Common Diseases

Butterfly bushes are generally resistant to most pests and diseases, but they may occasionally encounter issues that can affect their health and appearance. Being aware of common diseases and their symptoms can help you take proactive measures to care for your plants. Here are a few diseases that may affect butterfly bushes:

Powdery Mildew

Powdery mildew is a fungal disease characterized by a white, powdery growth on the plant’s leaves, stems, and flowers. It thrives in warm, humid conditions and can weaken the plant if left untreated. To prevent powdery mildew, ensure proper air circulation around the plant and avoid overhead watering, which can create conditions conducive to the disease. If detected, treat the plant with a fungicidal spray to control the spread of the fungus.

Gray Mold (Botrytis)

Gray mold, caused by the fungus Botrytis cinerea, can lead to the development of brown spots, wilting, and the decay of affected plant parts. This disease is prevalent in cool, damp conditions and can be particularly problematic in overcrowded plantings. To prevent gray mold, ensure proper spacing between plants, avoid overhead watering, and promptly remove and dispose of any diseased plant material to limit the spread of the fungus.

Root Rot

Excessive soil moisture or poor drainage can lead to root rot in butterfly bushes, resulting in wilting, yellowing leaves, and overall decline in plant health. To prevent root rot, ensure the soil is well-draining and avoid overwatering the plant. In cases of suspected root rot, carefully dig up the plant to assess the root system and take appropriate measures, such as adjusting the watering regime or replanting in well-draining soil.

Disease Diagnosis

Diagnosing diseases in butterfly bushes involves careful observation of the plant’s symptoms and, in some cases, examination of affected plant parts under magnification. Here are some steps to effectively diagnose diseases in your butterfly bush:

  • Visual inspection: Regularly inspect the plant for any unusual spots, discoloration, or growths on the leaves, stems, or flowers. Look for patterns of damage or discoloration that may help identify the underlying issue.

  • Leaf examination: Examine the undersides of leaves for signs of pest infestation or fungal growth, such as powdery mildew. Note any changes in leaf color, texture, or shape.

  • Stem and flower inspection: Check the stems and flowers for any abnormal growth, lesions, or discoloration. Look for any signs of rot or decay that may indicate a soil-borne disease.

  • Consulting resources: If you’re unsure about a particular symptom, consider reaching out to local gardening experts, extension offices, or plant clinics for assistance with disease diagnosis.

By carefully observing and documenting the plant’s symptoms, you can gather valuable information to aid in the accurate diagnosis of any potential diseases and take appropriate action to address the issue.

Common Pests

While butterfly bushes are relatively resistant to pests, they may occasionally encounter insect pests that can affect their growth and flowering. Being aware of common pests and their behaviors can help you implement effective pest control measures. Here are a few pests that may target butterfly bushes:


Aphids are small, soft-bodied insects that may gather in large colonies on the new growth of butterfly bushes, feeding on the plant’s sap and excreting honeydew. They can cause wilting, distortion of leaves, and stunted growth if left unchecked. To control aphids, spray the affected plant parts with a strong stream of water to dislodge the insects, or apply insecticidal soap or horticultural oil to eliminate them.

Spider Mites

Spider mites are tiny arachnids that feed on the underside of leaves, causing stippling, yellowing, and eventual leaf drop if left uncontrolled. These pests thrive in hot, dry conditions and can multiply rapidly under favorable conditions. Control spider mites by increasing humidity around the plant, spraying affected leaves with water to remove the pests, and applying miticides as needed to manage their population.


Certain caterpillar species may feed on the foliage of butterfly bushes, leading to defoliation and reduced plant vigor. While some caterpillars, such as those of the butterfly species the plant attracts, are desirable, others may be detrimental to the plant’s health. Handpick larger caterpillars and relocate them away from the plant, or use Bacillus thuringiensis (Bt) insecticides to target specific caterpillar species while sparing beneficial insects.

By monitoring your butterfly bushes regularly and taking prompt action to address any detected pest infestations, you can help protect the health and beauty of your plants.

Botanist’s Tips

As a plant scientist deeply passionate about butterfly bushes and their role in supporting biodiversity, I have gathered a few botanist’s tips to aid fellow gardeners in cultivating these magnificent plants and creating butterfly-friendly landscapes:

  1. Companion Planting: Pair the butterfly bush with other nectar-rich plants and host plants for caterpillars to create a diverse and vibrant habitat for butterflies and other pollinators. Consider including species such as coneflowers (Echinacea), milkweeds (Asclepias), and salvia varieties to provide additional forage and breeding sites for butterflies.

  2. Sustainable Garden Practices: Employ sustainable gardening practices, such as limiting the use of chemical pesticides and herbicides, to create a healthy and diverse ecosystem in which butterfly bushes can thrive alongside other plants and wildlife. Encourage natural predators of common pests to maintain the ecological balance in your garden.

  3. Observation and Record-Keeping: Take the time to observe the wildlife visiting your butterfly bushes and keep a gardening journal to document the butterfly species, bloom times, and other relevant observations. This can provide valuable insights into the effectiveness of your garden design in supporting local butterfly populations.

  4. Community Engagement: Share your passion for creating butterfly-friendly gardens with your community and inspire others to embrace biodiversity and conservation efforts. Consider organizing educational events, garden tours, or workshops to raise awareness about the importance of supporting pollinators through plant selection and habitat creation.

By incorporating these botanist’s tips into your gardening practices, you can contribute to the preservation of butterfly species and create an inviting and sustainable environment for these winged wonders to thrive.

Fun Facts

To further illuminate the unique appeal of the butterfly bush and its impact on the ecological landscape, here are some fascinating fun facts about this charming plant:

  • Aromatic Elegance: The flowers of the ‘Ellen’s Blue’ butterfly bush emit a lovely, sweet fragrance that acts as a natural draw for butterflies, providing both visual and olfactory delights in the garden.

  • Butterfly Galore: As its name suggests, the butterfly bush is a magnet for butterflies, attracting various species with its abundant nectar and providing a vital food source for these delicate creatures.

  • Educational Value: Butterfly bushes offer excellent opportunities for educational observations and studies, allowing enthusiasts of all ages to witness the life cycle of butterflies and gain a deeper appreciation for the natural world.

  • Ecological Impact: By supporting local butterfly populations through the cultivation of butterfly-friendly plants such as the butterfly bush, gardeners contribute to the broader conservation of pollinators and the essential role they play in maintaining healthy ecosystems.

  • Garden Spectacle: The vibrant, colorful flowers of the butterfly bush create a spectacle in the garden, drawing attention from humans and wildlife alike and adding a dynamic touch to any outdoor space.

Links to External Resources

To further enhance your understanding of the butterfly bush (Buddleja davidii ‘Ellen’s Blue’) and its role in butterfly-friendly gardening, I recommend exploring the following external resources for valuable insights and practical guidance:

By delving into these external resources, you can access a wealth of information, including plant care guidelines, ecological considerations, and expert recommendations to enrich your experience with the captivating butterfly bush.

As we’ve delved into the captivating world of butterfly bushes and explored the unique qualities and care requirements of the ‘Ellen’s Blue’ variety, I hope this comprehensive guide has equipped you with the knowledge and inspiration to embrace the beauty of these plants in your own garden or landscape. By nurturing butterfly bushes and creating butterfly-friendly habitats, you can play a vital role in supporting local pollinator populations and fostering biodiversity, all while enjoying the visually stunning blooms and enchanting charm of these remarkable plants. Happy gardening, and may your butterfly bushes flourish and flourish as they welcome an array of delightful winged visitors to your outdoor sanctuary.

Picture of Peter Taylors

Peter Taylors

Expert botanist who loves plants. His expertise spans taxonomy, plant ecology, and ethnobotany. An advocate for plant conservation, he mentors and educates future botanists, leaving a lasting impact on the field.