How to Grow Nanho Purple Butterfly Bush
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Nanho Purple Butterfly Bush
Buddleja davidii 'Nanho Purple'
shrubNanho Purple is a compact cultivar of butterfly bush known for its deep purple-violet flower spikes that bloom throughout summer and fall. This deciduous to semi-evergreen shrub attracts butterflies and pollinators while maintaining a manageable size of 4-6 feet tall and wide. It's prized for its long flowering season and ornamental garden appeal.
When should you plant Nanho Purple Butterfly Bush in your zone?
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Example Nanho Purple Butterfly Bush timeline · Pittsburgh, PA (Zone 6b)
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Plant Nanho Purple 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 Purple Butterfly Bush
Late summer into fallBefore the first fall frost (≈ Nov 8)
Sample dates for Pittsburgh, PA. Sign up to get exact Nanho Purple Butterfly Bush dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives best in zones 6-9; can survive zone 5b with winter protection
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Get my Nanho Purple Butterfly Bush timeline →Growth Stages
Establishment
3-6 monthsYoung transplant with developing root system and initial branching
Water regularly the first season to establish roots. Mulch around base. Prune lightly to encourage branching.
Vegetative Growth
4-8 weeksPlant rapidly develops stems and foliage, becoming fuller and bushier
Continue regular watering. Pinch back growing tips to promote bushier form. Apply balanced fertilizer monthly during growing season.
Budding & Flowering
3-4 weeksTerminal flower spikes form with tight clusters of purple-violet buds opening sequentially upward
Maintain consistent watering. Deadhead spent flower spikes to encourage continued blooming. Reduce nitrogen fertilizer to avoid excessive leafy growth.
Extended Bloom
12-16 weeksContinuous flowering from mid-summer through fall frost; fresh buds opening as lower flowers fade
Deadhead regularly for maximum blooms. Water moderately. Monitor for pests drawn to nectar-rich flowers.
Dormancy
3-4 monthsPlant gradually loses leaves and enters winter dormancy; may retain some foliage in mild climates
Cease fertilizing in late summer/early fall. Reduce watering significantly. Cut back old growth in early spring before new growth emerges.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Spray with water to dislodge; use insecticidal soap or neem oil if severe; improve humidity
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Use yellow sticky traps; spray with neem oil or insecticidal soap; encourage natural predators
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Prune heavily infested branches; apply horticultural oil in dormant season
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Ensure good air circulation; avoid overhead watering; apply sulfur fungicide if needed
Uses
Butterfly & Pollinator Magnet
WildlifeNanho Purple is renowned for attracting butterflies, bees, and hummingbirds throughout its extended bloom season. The abundant nectar-rich flowers provide essential food sources for pollinators during late summer and fall when other flowers may be scarce. [source]
Cut Flower & Floral Arrangements
HouseholdThe long, elegant purple flower spikes are excellent for fresh cut flower arrangements and bouquets. They last 7-10 days in water and add vertical interest and color to indoor displays. [source]
Traditional Herbal Tea
CulinaryIn traditional Chinese medicine, butterfly bush flowers have been used to make herbal infusions. The flowers may be dried and brewed, though culinary use is limited and should be researched for safety. [source]
Dried Flower Arrangements
CraftFlowers can be dried for long-lasting floral crafts, dried arrangements, and decorative displays. Cut spikes when fully open, hang dry in bundles in a warm, dark location. [source]
Landscape Ornamental & Privacy Screen
HouseholdIts compact size and dense foliage make Nanho Purple excellent for small gardens, borders, containers, and informal hedging. Multiple plants can create a colorful seasonal screen or backdrop. [source]
Harvest Tips
Deadhead spent flower spikes throughout the season by cutting just below the faded flowers to encourage continuous blooming. Prune back hard in early spring (before new growth) to maintain shape and rejuvenate old wood. Can be cut back to 12-18 inches annually. Harvest flowers for cutting when spikes are half-open for longer vase life.
Fun Facts
- 🌱 Nanho Purple is named after the Nanho District in Taiwan, where many dwarf butterfly bush cultivars were developed.
- 🌱 Despite its compact size, Nanho Purple produces as many flowers as its larger parent species, making it extremely prolific for the space it occupies.
- 🌱 Butterfly bush is considered invasive in some regions due to prolific seed production; Nanho Purple is less problematic than species plants, but deadheading prevents unwanted self-seeding.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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