Buddleja weyeriana
Buddleja weyeriana · Scrophulariaceae
📷 Ptelea · CC BY-SA 3.0
The gardener's calendar
Buddleja weyeriana is in full bloom: enjoy it, watch watering in hot weather and let spent flowers feed pollinators before pruning.
ID card
- Common name
- Butterfly bush
- Family
- Scrophulariaceae
- Form
- Shrub
- Adult height
- 2.5 m
- Foliage
- Semi-evergreen to deciduous
- Flowering
- July to September
- Ideal exposure
- Full sun
- Hardiness
- Moderate (-5 to -10°C)
✓ Taxonomy verifiedSource: AI estimate · hardiness: reliability medium.
Expert tips
The key tip
Prune Buddleja back to 30–50 cm at the end of winter (February-March) for abundant flowering in July. It starts from very little each spring, so hard pruning won't kill it—it's what revives it.
The common mistake
Not pruning hard enough in autumn or winter: the plant gets too tall, tired wood in the center, sparse flowering at the top.
The pro's trick
Spray with a potassium-rich fertilizer in early July when the first flower spikes appear: flowering lasts 2–3 weeks longer and flowers are denser.
Care
Watering
Keep the soil regularly moist during the growing season (spring-summer), especially the first two years after planting. Considerably reduce watering in autumn and winter. Avoid stagnant water which promotes root rot.
Exposure
Place your Buddleja weyeriana in full sun, ideally 6 to 8 hours per day. This exposure stimulates generous flowering and densifies the foliage. A location that's too shaded will produce fewer flowers.
Pruning
Prune after flowering (September-October) or in late winter (February-March) to maintain a compact shape. Remove dead or diseased branches, and cut back stems by 30 to 50 cm to encourage branching. This species can become invasive if not regularly controlled.
Soil and planting
Prefer well-drained soil, even poor or chalky; this shrub is very tolerant. Enrich lightly with compost at planting. Make sure water doesn't stagnate at the base, especially in humid regions.
Fertilizing
A moderate application of balanced fertilizer in spring (April-May) is plenty. Soil that's too rich encourages vegetation at the expense of flowers. No application needed after July.
Diseases and pests
This shrub is generally resistant. Watch for powdery mildew in case of excessive humidity; improve air circulation by removing dead wood. Few specific pests; a preventive copper treatment in spring can be useful in humid climates.
Did you know?
Buddleja weyeriana owes its nickname "Butterfly bush" to its magnetic appeal to these insects. The abundant nectar of its conical flowers in colored clusters (often yellow and orange for this species) attracts butterflies, bees and other pollinators, making it an essential element of wildlife gardens. In Asia, where it originates, this shrub has long been used both in ornamental gardens and traditional medicine.
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
- Butterfly bushBuddleja alternifolia
- Bride's SaddleDiascia rigescens
- Buddleja fallowianaBuddleja fallowiana
Tips generated and checked by Viridia — adapt them to your local climate.