Growing Hydrangeas in Pots: Choosing Varieties, Planting and Care
Hydrangeas grow well in pots when the variety, container and compost are chosen with their eventual size and moisture needs in mind. Learn how to plant, water, feed and protect...
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Buddleja davidii ‘Black Knight’
Butterfly Bush 'Black Knight'
I hold the RHS | Award of Garden Merit
Buddleja davidii ‘Black Knight’ is a vigorous butterfly bush with arching growth and long panicles of unusually deep purple, scented flowers on the current season’s shoots. Reaching around 3m if allowed to develop, it makes a strong back-of-border shrub and flowers best in a sunny, well-drained position, where the blooms are highly attractive to pollinating insects.
✅ Exceptionally dark purple scented flower panicles
✅ Nectar-rich flowers are excellent for pollinators
⚠️ Hard pruning each spring keeps growth manageable and floriferous
Plant Details
Flowering Months
Size
- Max Height
- 2.5 m — 4.0 m
- Max Spread
- 2.5 m — 4.0 m
- Growth Habit
- Densely branched plant with compact, leafy, rounded overall shape.
Planting Position
- Sunlight Indicates how much direct sunlight the plant needs each day. Full sun means 6+ hours, part shade is filtered or morning sun, and full shade is little to no direct sun.
- Full Sun Part Shade
- Aspect Aspect refers to the direction the planting spot faces (north, south, east or west). It affects light levels, warmth and exposure.
- South East West
- Exposure Exposure describes how sheltered or exposed a plant’s position is, particularly to wind and weather.
- Exposed / Sheltered
- Hardiness Hardiness indicates how well a plant tolerates cold conditions outdoors. Higher ratings generally mean greater frost tolerance.
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(−20 to −15 °C) Very cold-hardy
Ideal Soil Conditions
- Soil Type Soil type describes the texture of the soil (clay, sand, loam, chalk). This affects drainage, nutrients and how roots grow.
- Soil Moisture Soil moisture tells you how wet or dry the soil should be for best growth. Match this to your garden conditions for healthier plants.
- Moist but permeable / Free draining
- Soil pH Soil pH measures how acidic or alkaline the soil is. It affects nutrient availability and can impact plant growth.
Plant Uses & Merits
- Uses
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- Flower Borders
- Merits
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- Drought Resistant
- Fragrant
- Low Maintenance
- RHS | Award Of Garden Merit
- Loved By Pollinators
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