Skip to Content

What is a Dianella Plant?

A collage of different types of dianella plant.

Genus Dianella

The genus dianella is comprised of around 40 flowering plants in the asphodelaceae botanical family, which are mainly monocots. A monocotyledon is a type of flowering plant that produces stalkless leaves that bear a single seed; some examples of these are most grasses, palm trees or lilies.

Dianella is more commonly known as a flax lily. Flax lilies are a very sturdy perennial plant that can perform like an ornamental grass on your property. They are admired for their beautiful foliage primarily, but also for their dainty purple flowers and metallic berries.

The dianella is an absolute bargain when it comes to plants. It can thrive in shade, it doesn’t mind being crowded, it is tolerant of urban pollution, it’s deer resistant, and requires little to no maintenance. Keep reading to find out if the dianella will be the new plant in your garden!

Bright purple dianella berries growing on short stems with dark green blade like leaves in the background

Related: Purple Flowers | Berry FlowersSun-Loving Flowers | Water-Loving Flowers | Shade-Loving Flowers | Types of Flowers | Types of Flowers by Color | Types of Flowers by Alphabet | Types of Flower Colors

What are Some Dianella Species?

Tasmanian Flax Lily (Dianella Tasmanica)

Stunning light pink bell shaped flowers on the dianella plant with blurry green garden in the background

Also known as the Tasman flax lily, dianella tasmanica is a herbaceous perennial herb that is native to southeastern Australia.

These flax lily plants grow flower stems of up to 1.5 metres in height that bear blue star shaped flowers in the spring. In the summer it will bear violet berries. Leaves are keeled with finely toothed margins.

Blue Flax Lily (Dianella Revoluta)

Bright purple flower with yellow anthers of the black anther flax lily growing at the end of a long stem

Also known as the black anther flax lily, dianella revoluta is a tufted perennial herb that is endemic to Australia and grows prosperously there.

This dianella variety grows folded, grass like leaves that can be up to 33 inches tall. Flower stems only reach about 6 inches in height and bear blue or violet flowers that are borne in clusters of 9. Flowers occur in the spring which bring about purple berries in the summer.

Blue berry Lily (Dianella Caerulea)

Light blue flowers with bright yellow anthers of the blue berry flax lily growing at the end of a long stem

Also known as the paroo lily, dianella caerulea is native to the eastern side of Australia and Tasmania.

This species is a scrappy perennial plant that grows to be nearly 1 metre tall with dark green bladed leaves with toothed margins. It bears small blue flowers in the mid spring and indigo berries in the summer.

Cerulean Flax Lily (Dianella Ensifolia)

Stunning indigo berries of the cerulean flax lily plant with blurred green background

Dianella ensifolia is an evergreen perennial herb that is native to southern Africa, and subtropical Asia in the Philippines and Indonesia.

This plant grows grass like leaves that can achieve heights of 1.5 metres with finely serrated margins. It bears either white flowers or yellow flowers in the spring and bright blue berries in the summer months.

What do Dianella Plants Look Like?

Flowers

Dianella flowers are borne in the spring time and emerge as star shaped flowers with 3 sepals (that look and act just like 3 petals). At the centre lies golden colored anthers. Flowers will usually bloom in early spring to mid spring.

Flowers are usually blue or purple, though some cultivar types bear white flowers. Flowers are bisexual and contain one superior ovary. The dianella plant, once pollinated, will produce fruit in the form of small berries that range in blue or purple colors.

White star shaped flower with yellow anthers of the dianella plant

Leaves

Though dianella flowers are lovely, these plants are more valued for their incredibly ornamental foliage. Blade-like leaves fan out from a central clump, and each leaf can grow to be up to 30 inches in height!

These usually linear leaves have overlapping bases. Leaves are usually a light green, though they can sometimes be dark green, they can have white striped accents or purple striped accents too!

This effect of two tones on a leaf is called variegation. A variegated flax lily plant will have different colors on various areas of the stems and leaves of the plant.

Growth Pattern

The dianella grows from rhizomes, which are bulbous roots that grow underground (similar to iris‘). They grow very vigorously from these rhizomes and they will proliferate exuberantly with regular watering.

From a rhizome grows long bladed leaves and flower stalks that bear that star shaped flowers. Heights will vary depending on the dianella species, but many will grow to be over 1 metre tall.

Beautiful variegated leaves of green and white of the dianella plant growing in a rock garden

Where is Dianella Native to?

Dianella plants occur naturally in Africa, southwestern Asia, the Pacific Islands, and New Zealand and Australia as well. They tend to grow most prosperously in Australian regions like Tasmania and the moist shaded forests of Victoria.

These plants are quite cold hardy as well and can exist in USDA growing zones 7 through 11 throughout the world. As long as they receive a certain amount of shade and water, they will grow happily.

How do you Grow a Dianella?

Dianella is a perfectly low maintenance plant. If you happen to be looking for something that is easily maintained, doesn’t need regular pruning, doesn’t have specific growing requirements, and still produces attractive foliage, flowers, and fruit, the dianella is the plant for you!

Propagation can be done either from collecting ripe seeds and sowing them by hand, or by collecting rhizomes and dividing them in the spring.

The first step is to pick the ideal place on your property. Ensure the area has a minimum of light shade, and that the soil is moderately well drained. If soil is low in nutrients, simply incorporate compost or manure to increase its quality.

If propagating through rhizome division, plant the rhizome 6 inches deep in the soil with the eye of the bulb pointing up. It should begin taking root within a few short weeks. It is advised to water young plants generously until they are well established, where they will then be drought tolerant.

If planting from seed, ensure that seeds aren’t pushed too deep into the soil and that only a light layer of soil is covering them. They require a certain amount of sunlight during their establishment period. Take care not to water directly onto the soil so as to not dislodge the seeds.

Beautiful long sword like leaves growing in clusters with purple flowers in bloom of the dianella plant

What are the Growing Conditions of Dianella Plants?

Soil Type

Dianella plants can tolerate many soil types. They are entirely tolerant of clay soil and sandy soil, and are tolerant of temporarily waterlogged soils as well. That being said, they perform best in well drained soil.

Sun Exposure

Dianellas prefer to exist in partial shade conditions or in full shade conditions. They will still be able to produce productive flower blossoms in light shade.

Water Level

Well established dianella plants are drought tolerant as long as it is temporary. Their native growing regions experience frequent drought, and this is a good indicator of how often they should be watered.

Dianellas do not need to have completely moist soil in order to thrive. It is safe to wait until soil has completely dried out before watering again.

Closed flower buds of a light purple flower on a dianella plant at the ends of long stems

Temperature

Dianellas are a rather cold hardy plant and will survive unexpected frost. They are cold hardy until about 20 degrees Fahrenheit, and exist in USDA growing zones 7 through 11.

Pruning

The dianella responds very well to pruning, and it helps the plant grow more vigorously the following growing season.

Expired leaves can be pruned whenever they appear, and the removal of spent flowers will help keep the plant happy as well. Prune the spent flowers and their stems, as they will re-sprout the following year.

Fertilizer

A dianella plant only needs to be given fertilizer if it exists in very poor nutrient soil. This needn’t be done with liquid fertilizer, but instead the soil can be incorporated with compost or manure.

Intolerances

At the end of the day, the dianella plant is an extremely resilient plant that is wonderfully low maintenance. Once it is established in your garden it will spread and keep flowering year after year. It does not have any true intolerances, only preferences.

Big clusters of of long green blade like leaves growing in a large field of the dianella plant

How is the Dianella Plant Used?

Ornamental Plant

Dianella plants are grown for their star shaped blue flowers and as equally charming berries, but their main attraction is their attractive foliage (and of course drought tolerance).

They bring a tropical appearance to a garden landscape and are often used for mass planting under large tree species (as they are wonderfully shade tolerant).

They make wonderful companion plants for hibiscus species and hosta species, and add foliage interest to container plant combinations. Thought it won’t be the centrepiece of a garden, it makes for a wonderful accent plant.

Ethnobotany

Dianella foliage have been used by Australian indigenous peoples for weaving materials in order to create baskets and dillies (traditional woven bags).

White and green clusters of sword leaves of the dianella plant growing in moist soil in a garden

FAQs