Butterfly bush
Buddleja alternifolia · Scrophulariaceae
📷 Wouter Hagens · Public domain
The gardener's calendar
In autumn, ease off feeding and take the chance to clean up around butterfly bush and prepare for winter.
ID card
- Foliage
- Deciduous, narrow and lanceolate
- Flowering
- April to June, clusters of small, highly fragrant violet or mauve flowers
- Mature size
- Up to 3–4 m tall, spreading and arched habit
- Growth
- Fast to very fast
- Hardiness
- Good, tolerates down to around −15 °C
- Origin
- China, Yunnan region
- Soil type
- Well-drained soil, tolerates poor and chalky soils
✓ Taxonomy verifiedSource: AI estimate · hardiness: reliability high.
Expert tips
The key tip
Buddleja alternifolia displays its flowers on the previous year's branches. Plant it in well-draining soil and mulch lightly.
The common mistake
Hard pruning in winter: you'll remove the flowering branches.
The pro's trick
Lightly pinch back young shoots in April to encourage branching.
Care
Sunlight
Place your Buddleja in full sun for abundant flowering and compact growth. It also tolerates partial shade, but flowering will be less generous. Avoid dense shade areas that slow growth.
Watering
Water moderately, particularly during spring growth and prolonged dry spells. Once established, this plant tolerates drought well. Avoid excess water that promotes root rot.
Pruning and maintenance
Prune lightly after flowering (July–August) to maintain balanced, dense growth. You can also cut back the wood more severely in late winter if the plant becomes too large. Remove dead or poorly oriented branches.
Soil and drainage
Buddleja alternifolia prefers well-drained, low-fertility soil. It adapts to chalky and poor soils. Enrich the soil slightly at planting time, but don't add too much organic matter, as this will encourage growth at the expense of flowering.
Fertilization
An annual application of balanced fertilizer in spring is more than sufficient. Avoid excess nitrogen, which causes excessive growth at the expense of flowers. A moderately fed plant will flower more generously.
Diseases and pests
Buddleja alternifolia is generally robust. Watch for aphids on young shoots and possible cankers or root rot in very humid conditions. Good foliage aeration and optimal drainage prevent most problems.
Did you know?
Buddleja alternifolia is nicknamed the 'butterfly tree' because of its remarkable ability to attract butterflies and pollinating insects, particularly in June. Originating from the mountains of Yunnan in China, it was introduced to Europe in the early twentieth century and has become a major ornamental plant thanks to its gracefully arched habit and intensely fragrant flower clusters.
Where to buy it
Best planted in autumn so the roots settle in before summer, or in early spring once the frost has passed. Pick a plant with healthy foliage and roots that are not exposed. Best time: March, October, November.
Add this plant to my garden →Plants from the same family
- Butterfly bushBuddleja davidii
- Texas barometer bushLeucophyllum frutescens
- Buddleja virgataBuddleja virgata
- Buddleja fallowianaBuddleja fallowiana
- Buddleja weyerianaBuddleja weyeriana
- Bride's SaddleDiascia rigescens
Tips generated and checked by Viridia — adapt them to your local climate.