How to Grow Nanho Blue Butterfly Bush
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Nanho Blue Butterfly Bush
Buddleja davidii 'Nanho Blue'
shrubNanho Blue is a compact cultivar of butterfly bush known for its deep blue-purple flower spikes and dwarf growth habit, typically reaching 4-6 feet tall. This deciduous to semi-evergreen shrub blooms prolifically from summer through fall, attracting butterflies and other pollinators. It's a smaller alternative to standard butterfly bush varieties, making it suitable for smaller landscapes and containers.
When should you plant Nanho Blue Butterfly Bush in your zone?
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Example Nanho Blue Butterfly Bush timeline · Pittsburgh, PA (Zone 6b)
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Plant Nanho Blue Butterfly Bush
Around Apr 17Near Pittsburgh's average last spring frost.
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Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
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Harvest Nanho Blue Butterfly Bush
Around Jun 16≈ 60 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Nanho Blue Butterfly Bush dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 6-9; hardy to zone 5b with winter protection
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Get my Nanho Blue Butterfly Bush timeline →Growth Stages
Establishment
2-4 weeksYoung transplant settling in with initial leaf growth and root development
Water regularly but allow soil to dry slightly between waterings. Mulch around base. Protect from harsh wind. Remove any dead or damaged branches.
Vegetative Growth
4-6 weeksVigorous shoot and leaf development with elongating branches and increasing foliage density
Pinch back new growth in late spring to encourage bushier form. Fertilize monthly with balanced fertilizer. Water moderately. Remove lower weak growth.
Flowering
8-12 weeks (summer through fall)Characteristic long, dense flower spikes in deep blue-purple color appearing at branch tips
Deadhead spent flower spikes regularly to encourage continuous blooming. Provide consistent watering. Watch for spider mites in hot, dry conditions. Light weekly fertilizer boosts flowering.
Post-Bloom & Dormancy
2-4 monthsFlowers fade and cease production as temperatures cool; plant begins to slow growth and prepare for winter
Reduce watering frequency. Do not fertilize. In zones 5-6, provide winter mulch around base. In cooler zones, plant may die back to ground level—cut to 6-12 inches in early spring.
Spring Renewal
3-4 weeksNew shoots emerge from base or existing branches as temperatures warm; foliage returns
Remove any winter-killed wood. Prune to desired shape in early spring before growth begins. Begin regular watering and fertilizing as new growth appears.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Increase humidity with misting; spray with strong water jet; use miticide if severe. Improve air circulation.
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Use yellow sticky traps; spray with insecticidal soap or neem oil; remove heavily infested leaves.
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Spray with water or insecticidal soap; introduce beneficial insects like ladybugs; prune affected growth.
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Hand-pick early morning; use pheromone traps away from plant; apply neem oil; avoid trap placement near shrub.
Uses
Butterfly & Pollinator Magnet
WildlifeNanho Blue is renowned for attracting butterflies, moths, bees, and hummingbirds with its abundant fragrant flower spikes. It serves as an excellent nectar source throughout the long bloom season. [source]
Ornamental Landscaping
HouseholdThe compact 4-6 foot form makes it ideal for small gardens, mixed borders, foundation plantings, and container gardening. Deep blue-purple flowers provide season-long color contrast. [source]
Edible Flowers
CulinaryThe flowers are edible and can be used as a decorative and mildly sweet garnish for desserts, salads, and beverages, though flavor is subtle. [source]
Traditional Herbal Use
MedicinalIn traditional Chinese medicine, Buddleja davidii is used in herbal remedies, though scientific evidence is limited. Modern herbal practitioners sometimes use it for respiratory support. [source]
Cut Flowers & Arrangements
CraftLong-lasting flower spikes make excellent cut flowers for fresh arrangements and dried flower crafts. They add vertical interest and color to floral designs. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Deadhead spent flower spikes just below the faded flowers to encourage new blooms throughout the season. Cut flower spikes for fresh bouquets anytime during active blooming. In early spring, prune back to 12-18 inches to maintain compact shape and promote bushier growth.
Fun Facts
- 🌱 Nanho Blue was bred to be a non-invasive, sterile cultivar—standard butterfly bush produces seeds that spread readily and is considered invasive in many regions, but Nanho Blue's reduced seed production makes it a more responsible garden choice.
- 🌱 The plant got its name 'butterfly bush' because it attracts more butterfly species than nearly any other ornamental shrub; it's also called 'summer lilac' because its fragrant flower spikes resemble lilac blooms.
- 🌱 Buddleja davidii is native to China and was introduced to Europe in the 1890s; it has become naturalized in many temperate regions worldwide, with some populations becoming problematically invasive in sensitive ecosystems.
Gardening Terms
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