Overview
Dianella caerulea is a perennial herb in the genus Dianella, part of the Asphodelaceae family. It typically grows around 0.8 m tall. Dianella caerulea grows best in full sun, and tolerates sandy and loamy soils. Its UK hardiness is rated H4. It is native to Australia and New Guinea.
About the genus
Dianella is a genus of about forty species of flowering plants in the monocot family Asphodelaceae, commonly known as flax lilies. Plants in this genus are tufted herbs with more or less linear leaves and bisexual flowers with three sepals more or less similar to three petals and a superior ovary, the fruit a berry. They occur in Africa, South-east Asia, the Pacific Islands, New Zealand and Australia.
Wikipedia contributors, "Dianella (plant)", CC BY-SA 4.0 — Dianella (plant)
In the garden
Dianella caerulea is a perennial herb native to Australia and New Guinea, growing to around 0.8 m. In the UK it flowers from June to August and later produces ornamental fruit; the plant's habit and size make it a measured, architectural element in planting schemes rather than a ground cover. Place it in full sun on sandy or loamy soil that drains well; the species tolerates moist but well-drained conditions rather than waterlogged ground. It is classed H4 (average) on the UK hardiness scale, so it withstands normal UK winter conditions in many areas; the USDA hardiness range is 8–11 where those zones apply. Use Dianella caerulea where a sun-loving, mid-height perennial is required — for sunny beds and mixed borders that have good drainage. It will sit comfortably beside other sun-tolerant herbaceous plants or in larger containers where root space and drainage are adequate. Take care when cutting back or handling ripe fruit: the berries are ornamental and not to be eaten, and protective gloves are recommended when working with the plant.
Growing conditions
Best soil and position for Dianella
- Sunlight
- Full sun
- Soil type
- Sandy, Loamy
- Soil moisture
- Well-drained, Moist but well-drained
- UK hardiness
- H4
Plant details
Dianella caerulea size, habit and characteristics
- Plant type
- perennial herb
- Height
- 0.8 m
- Native to
- Australia, New Guinea
- Toxicity
- Fruit are ornamental - not to be eaten. Wear gloves and other protective equipment when handling Pets: Fruit are ornamental - not to be eaten - see the HTA guide to potentially harmful plants for further information and useful contact numbers
Frequently asked questions
Where is the best place to plant Dianella caerulea?
Dianella caerulea prefers full sun.
What soil does Dianella caerulea need?
Dianella caerulea grows best in sandy and loamy soil. Aim for soil that stays well-drained to moist but well-drained.
How big does Dianella caerulea grow?
Dianella caerulea reaches a height of 0.8 m.
Is Dianella caerulea hardy in the UK?
Dianella caerulea has an RHS hardiness rating of H4, meaning it is hardy through an average UK winter, tolerating -10 to -5°C.
Is Dianella caerulea toxic?
Fruit are ornamental - not to be eaten. Wear gloves and other protective equipment when handling Pets: Fruit are ornamental - not to be eaten - see the HTA guide to potentially harmful plants for further information and useful contact numbers.
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