Dianella caerulea Cassa Blue ('Dbb03'PBR)
flax lily [Cassa Blue]
A compact, half-hardy evergreen perennial to 40cm high, with dense clumps of narrow, stiff, grass-like blue-green leaves. In early to mid summer, produces sprays of nodding light blue flowers with conspicuous yellow anthers, held on branched stems high above the foliage. These are sometimes followed by round blue-purple berries
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Size
Ultimate height
0.5–1 metresTime to ultimate height
2–5 yearsUltimate spread
0.1–0.5 metresGrowing conditions
Moisture
Well–drainedpH
Neutral, AcidColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Blue Green | |||
|---|---|---|---|---|
| Summer | Blue | Blue Green | ||
| Autumn | Blue Green | Blue Purple | ||
| Winter | Blue Green |
Position
- Full sun
- Partial shade
Aspect
South–facing or West–facing
Exposure
Exposed or Sheltered Hardiness
H3Botanical details
- Family
- Asphodelaceae
- Native to GB / Ireland
- No
- Foliage
- Evergreen
- Habit
- Tufted, Clump forming
- Potentially harmful
- Fruit are ornamental - not to be eaten. Wear gloves and other protective equipment when handling
- Genus
Dianella are rhizomatous evergreen perennials with leathery, sword-shaped leaves and sprays of small, starry deep blue flowers followed by long-lasting blue or purple berries
- Name status
Trade
How to grow
Cultivation
In milder areas, grow outdoors in moderately fertile, well-drained, neutral to acid soil in full sun or partial shade. In areas prone to hard frosts, grow under glass in peat-free, loam-based compost, in full light with shade from hot sun. Water well in growth and keep just moist in winter.
Propagation
Propagate by division of rhizomes in mid-spring
Suggested planting locations and garden types
- City and courtyard gardens
- Cottage and informal garden
- Coastal
- Patio and container plants
- Flower borders and beds
- Conservatory and greenhouse
Pruning
No pruning required
Pests
Generally pest-free
Diseases
Generally disease-free
Get involved
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