Dianella: Planting, Growing and Care

Botany

Dianella are rhizomatous perennials comprising around forty species, about half of which are native to Australia. The others originate from New Zealand, eastern Africa, Madagascar, Southeast Asia and the Pacific Islands. They mainly grow in woodland undergrowth, as well as in scrubland and heathland. The most commonly cultivated are Dianella revoluta and Dianella tasmanica, native to Australia and Tasmania. There are also numerous varieties, prized for their foliage in varying hues.

Dianella ensifolia: Botanical illustration

Dianella belongs to the Xanthorrhoeaceae botanical family. This family includes ornamental plants with a very exotic style, such as Kniphofias, Daylilies, Foxtail Lilies, Aloes, New Zealand Flax, Asphodels, Bulbines and Haworthias.

Dianella was named after the Roman goddess Diana. The suffix ella means “small”. The species name Dianella tasmanica refers to its geographical origin: Tasmania. As for Dianella caerulea, its species name means “blue”, alluding to the flowers and berries.

Dianella form clumps of broad, slender leaves, resembling those of Irises. They reach between 40 and 80 cm in height, sometimes up to 1.20 m. Smaller varieties create a stunning effect when planted en masse. Dianella has an underground rootstock, allowing the clumps to gradually expand.

Dianella in flower (photos: Adobe Stock / David Francis 34 / Louise Docker)

Dianella flower in late spring or summer, between May-June and August depending on the species. They then produce loose, very airy panicles, branched, 40 to 60 cm long. These bear small star-shaped blue flowers with yellow stamens. The flowers measure 1 to 2 cm in diameter and consist of three petals and three blue sepals, all looking alike (referred to as tepals). They feature six central yellow stamens, also very decorative, along with a central pistil. The blue petals curve backwards from the flower, in the opposite direction to the stamens. The delicacy and lightness of the flowers create a beautiful contrast with the massive, stiff, linear foliage. Dianella flowers are pollinated by insects, which carry pollen from the stamens to the flower’s pistil, enabling the plant to reproduce.

Dianella has highly graphic foliage. It consists of long, ribbon-like, upright leaves, resembling those of Phormiums. The leaves are broad and stiff, with rough-edged lamina. They measure between 50 cm and 1.20 m long and have a prominent central vein, parallel to the edge of the lamina. Depending on the variety, leaves can be stiff and upright (as in Dianella ‘Little Rev’) or very flexible and arching, as in Dianella ‘Emerald Arch’ or ‘Blaze’. The leaves are evergreen, ensuring year-round presence in the garden, even in winter.

Foliage of Dianella ‘Breeze’, Dianella tasmanica var. variegata and Dianella tasmanica (photos: Jason Baker / David J. Stang / Daderot)

Dianella leaves come in a wide range of hues depending on the variety. For example, Dianella tasmanica ‘Variegata’ has beautifully variegated white foliage, very luminous. Conversely, Dianella tasmanica ‘Blaze’ offers very dark, chocolate-brown foliage. Dianella ‘Cassa Blue’ has attractive blue-tinged foliage, while Dianella ‘Tas Red’ leaves are bicoloured: red at the base and green on the rest of the lamina. Dianella tasmanica ‘Rainbow’ is one of the most colourful: leaves are green variegated with creamy yellow and tinged red at the base. ‘Rainbow Twist’ has grey-blue leaves edged with red-pink, with hues changing through the seasons.

Dianella is among the few perennials with decorative berries. In autumn, the flowers give way to ovoid dark blue to violet berries, shiny, measuring 1 to 1.5 cm in diameter. They contain black seeds, which can be collected to propagate the plant by sowing.

The blue-violet berries of Dianella (photo: Adobe Stock)

The main varieties of Dianella

The Most Popular Varieties

Our Favourite Varieties

Dianella revoluta Little Rev

This is a compact variety, forming small clumps of stiff, upright leaves in a blue-grey-green colour. It resembles a grass but lights up in summer with numerous small blue flowers. It looks best when planted en masse.

• Flowering time July to September
• Height at maturity 40 cm

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Dianella revoluta Coolvista

This variety forms clumps of fine, upright leaves in a beautiful blue-grey hue. It will easily find its place in a modern, graphic-style garden.

• Flowering time July to September
• Height at maturity 60 cm

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Dianella tasmanica Variegata

A larger variety than the previous ones, also distinguished by its bright white-variegated green foliage. The leaves are arched, trailing at the tips.

• Flowering time June, July
• Height at maturity 80 cm

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Dianella tasmanica Blaze

An original variety with chocolate-brown foliage, forming small, soft, arched clumps that beautifully highlight and contrast with its blue flowering.

• Flowering time June to August
• Height at maturity 45 cm

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Dianella tasmanica

This is the botanical species, as found in the wild. It bears long, bright green leaves and also produces beautiful star-shaped blue flowers with yellow stamens, followed by blue-purple berries.

• Flowering time June, July
• Height at maturity 80 cm

See the product sheet

Planting

Where to Plant?

In the warm regions of southern France, particularly along the Mediterranean basin, we recommend planting Dianella in shade or partial shade. In Australia, its natural habitat is typically undergrowth, so it thrives in shaded spots. Intense sunlight could damage its foliage. However, in the northern half of France, where temperatures are cooler, we advise planting it in full sun as it requires warmth. In any case, choose a location sheltered from cold winds. Dianella is not a very hardy plant (though it can reportedly withstand temperatures down to –12°C in sheltered, well-drained conditions): outside the Atlantic coast and the Mediterranean basin, it will need winter protection—either by wrapping it in horticultural fleece and mulching thickly around the clump or by growing it in a pot and moving it under cover for winter.

Dianella is particularly well-suited to coastal gardens, as it tolerates sea spray well.

Regarding soil type, the most important factor is ensuring excellent drainage, as waterlogged conditions could cause root rot. If your soil tends to retain moisture, improve drainage by mixing gravel or coarse sand into the planting hole. You can also plant it on a mound to encourage rapid water runoff. Dianella also thrives in fertile, humus-rich soil. Don’t hesitate to add well-rotted compost at planting time. Finally, it dislikes chalky soils: it requires a neutral or acidic substrate.

Dianella fits seamlessly into Mediterranean or exotic-style gardens. Varieties with brown foliage (like Dianella ‘Blaze’) or variegated leaves (Dianella tasmanica ‘Variegata’) work beautifully in contemporary, architectural gardens. Dianella can be planted in raised rockeries for ideal drainage and makes a striking border along pathways. Taller varieties can be planted singly or in small groups—for example, near a house entrance or along a short grass meadow to showcase their bold foliage—while compact varieties like Dianella ‘Little Rev’ create the most impact when planted en masse.

When to Plant?

Plant Dianella in spring, in April or May, once the risk of frost has passed.

How to Plant?

In the ground:

1. Dig a planting hole, roughly twice the size of the root ball.
2. Backfill with soil mixed with well-rotted compost, adding gravel or coarse sand if needed to improve drainage.
3. Remove the Dianella from its pot and place it in the hole.
4. Backfill with soil.
5. Water thoroughly.
6. We recommend applying an organic mulch around the clump. This helps retain soil moisture (reducing watering needs) while suppressing weeds.

In pots:

1. Choose a pot with drainage holes.
2. Add a layer of gravel or clay pebbles at the base.
3. Fill with a well-draining, non-chalky substrate. For example, mix potting compost, garden soil, coarse sand, and optionally some heather soil.
4. Remove the Dianella from its original pot and position it centrally in the new container.
5. Fill around the root ball with more compost.
6. Water generously.

Place the pot in sun or partial shade, sheltered from cold winds.

Dianella tasmanica

Maintenance

In the Ground

Water regularly in the weeks following planting to help the plant establish well and develop its root system. If your water is hard, use rainwater if possible. Once established, Dianella tolerates summer drought well and can go without watering. However, you can apply a layer of mulch around the clump to keep the soil moist for longer.

Don’t hesitate to protect Dianella from cold in winter by wrapping it in horticultural fleece and spreading a thick layer of mulch around the clump.

Do not cut back faded flower spikes, or your Dianella won’t produce berries! After pollination, the flowers may give way to stunning metallic blue berries.

Dianella is not particularly prone to diseases or parasitic pests.

In Pots

In cooler regions, grow Dianella in pots and bring it under cover in autumn. Place it in a bright but not too warm spot, such as a conservatory or unheated greenhouse kept frost-free. You can move it back outdoors the following spring, once the risk of frost has passed.

If growing Dianella in a pot, remember to water it regularly (once or twice a week) in spring and summer. You can reduce watering in autumn and winter. Preferably use rainwater. Avoid leaving standing water in the saucer. We also recommend applying some fertiliser to support growth and flowering. For example, use a liquid fertiliser, diluted in the watering can.

Propagation

Sowing

To carry out the sowing, you can pick the blue berries when they are fully ripe and then extract the seeds they contain. Germination appears to be aided by soaking the seeds in water for 24 hours.

1. Prepare pots by filling them with seed compost.
2. Lightly firm and level the surface of the compost.
3. Sow the seeds.
4. Cover with a thin layer of compost.
5. Water gently with a fine spray.
6. Place the pots in a sheltered, bright location out of direct sunlight, ideally at a temperature between 13 and 16°C. Temperatures above 18°C may inhibit germination.

Keep the substrate slightly moist until germination, which usually occurs after 2 weeks but may take longer. You can transplant the seedlings into individual pots once they reach a size that allows for easy handling. Wait until the following spring before planting them in the garden.

Division of Clumps

Dianella is a perennial with a rootstock, so it can be easily divided. Compared to sowing, division allows you to obtain new young plants ready for the garden more quickly and simply. We recommend doing this in spring.

1. Choose a healthy, well-established Dianella clump and carefully dig it up by loosening the soil around it.
2. Remove excess soil if necessary to expose the roots and rootstock.
3. Divide the clump into several sections by cutting through the rootstock. Ensure each section retains roots.
4. Replant in a new location after preparing the soil, or in pots.
5. Water generously.

Association

As it is particularly suited to mild coastal climates, you can incorporate Dianella into a Mediterranean-style garden. It will be perfect at the foot of the majestic silhouette of an olive tree, with dark-leaved varieties like Dianella ‘Blaze’ creating a stunning contrast with its silvery-grey foliage. Also consider rockroses, strawberry trees, fig trees, palms and oleanders! Add aromatic plants like lavenders, thymes, rosemaries, cotton lavenders and curry plants. Bring in colour with the flowering of Phlomis fruticosa, agapanthus, ice plants and rockroses.

Dianella integrates easily into a Mediterranean-style garden. Here, Agapanthus ‘Royal Velvet’, Dianella tasmanica (photo Adobe Stock), Nerium oleander ‘Emilie’, Agave americana ‘Variegata’, Helianthemum ‘Ben Fhada’ and Lavandula angustifolia ‘Hidcote’

Native to the Southern Hemisphere, particularly Australia, Dianella will naturally find its place in an exotic garden. Don’t hesitate to pair it with Australasian plants! Consider for example the graphic foliage of New Zealand flax, Cordyline australis and Carex comans ‘Bronze Form’. These foliage plants will create a superb setting to highlight the flowering of Dietes bicolor, red hot pokers, montbretias, pineapple flowers and the highly original Anigozanthos. Also discover Tigridia pavonia, nicknamed Peacock Flower, a lovely bulb that produces white, yellow or red summer flowers with triangular corollas and purple-tiger-striped throats.

Discover our inspiration page “Australian Exoticism”

Dianella helps create a beautiful “Australian Exoticism” style atmosphere in the garden. Crocosmia ‘Sunglow’, Dianella longifolia (photo Adobe Stock), Kniphofia ‘Fiery Fred’, Eucomis ‘Sparkling Rosy’, Anigozanthos and Phormium ‘Pink Panther’

The Dianella tasmanica ‘Blaze’ and ‘Variegata’, with their chocolate-brown or white-variegated foliage, are perfect for a graphic, contemporary garden. Create a garden with clean lines, well-defined borders, stepping stone pathways and pruned bushes (box, Ilex crenata, Lonicera nitida…). We recommend favouring sober, elegant tones rather than bright colours: opt for white, purple, black and bronze… Enjoy the highly graphic flowering of Allium schubertii, Echinops ‘Star Frost’, and agapanthus ‘Black Magic’ or ‘Glacier Stream’. You can also incorporate some ornamental grasses like fountain grasses or feather grasses: their fine foliage and light spikes will create a lovely contrast.

You can also pair Dianella with other perennials and decorative fruit bushes. Consider for example beautyberries, snowberries, spindle trees, viburnums, Liriope muscari and Maianthemum bifolium.