Tasmanian or Tasman Flax Lily

Dianella tasmanica, also known as the Tasmanian Flax Lily, Flax Lily, or Blue Berry Flax Lily, is a perennial plant native to the shaded forests of Tasmania, Victoria, and the east coast of New South Wales, Australia.
This clumping, evergreen plant is prized for its attractive, strap-like foliage, delicate flowers, and striking blue berries. First collected by botanist Ronald Gunn in 1837, it has since become a popular choice in gardens for its low-maintenance nature and tolerance to various growing conditions.
The plant produces long, narrow leaves with red-edged tips that create a unique visual appeal. In spring to summer, Dianella tasmanica produces small clusters of lavender to violet flowers with yellow stamens, which are followed by its iconic blue berries. These berries, typically bird-dispersed, are often used by Aboriginal Australians to dye materials such as Lomandra leaves for basket weaving.



Growing Conditions for Dianella tasmanica – Basic Care
Dianella tasmanica thrives in environments that mimic its native shaded or partially shaded habitats. While it can tolerate full sun, it is best suited to areas with some shade to protect it from scorching midday sun, especially in hotter climates.
This hardy plant is adaptable to a variety of soil types, but it prefers well-drained soil that is not too alkaline.
The plant’s drought tolerance and frost resistance make it ideal for gardens in variable climates. Once established, Dianella tasmanica requires minimal care, making it an excellent choice for low-maintenance and low-water gardens.
Planting Dianella tasmanica
- Choose a location with partial shade or full sun (depending on your climate).
- The plant is best grown in well-draining soil with a pH level ranging from neutral to slightly acidic (6.0–7.5).
- Prepare the planting area by weeding well, digging a hole that is twice as wide as the root ball but no deeper. Add organic matter such as compost to improve soil structure and ensure good drainage.
- Space plants about 45–60 cm (18–24 inches) apart to allow for clump growth.
- Planting in groups will creates a better visual impact.
- Watering
While Dianella tasmanica is drought-tolerant once established, it benefits from regular watering, especially during prolonged dry spells. Ensure the soil is moist but well-drained. Deep watering encourages the development of deep roots. Avoid overwatering or waterlogging, as this can lead to root rot. - Light Requirements
This plant performs best in partial shade but can tolerate full sun in cooler climates. In regions with hot summers, afternoon shade is ideal to protect the leaves from sunburn. Dianella tasmanica adapts well to lower-light conditions, making it suitable for planting beneath large trees or in woodland-style gardens. - Temperature and Humidity
Dianella tasmanica is highly adaptable to various climates. It can thrive in cool to moderate climates, withstanding frostonce established (hardy to USDA zones 9–11). In warmer regions with humid summers, it grows best in shaded areas, where it benefits from higher humidity. While the plant is resistant to cold, it may require additional care during extreme heat or prolonged drought. - Soil and Potting Mix
This plant requires well-draining, moist soil enriched with organic matter. It thrives in slightly acidic to neutral soil (pH 6.0–7.5). If growing in containers, choose a well-draining potting mix and ensure the pot has adequate drainage holes to prevent water from accumulating around the roots. - Fertilising
To encourage healthy growth and vigorous flowering, apply a balanced, slow-release fertiliser in early spring.
Avoid over-fertilising, as this may result in excessive leaf growth with fewer flowers and berries. Organic compost or well-rotted manure can also be used to improve soil fertility and ensure long-term plant health. - Repotting and Dividing
Dianella tasmanica can be grown in pots, but it may need to be repotted or divided every few years to prevent overcrowding.
Repotting is best done in spring when the plant begins its growth phase. When dividing, ensure that each new clump has both roots and shoots. Choose a larger pot to allow the plant to continue growing.
Pruning
Dianella tasmanica requires minimal pruning.
- Removing any dead or damaged leaves is recommended to maintain its appearance and encourage healthy growth.
- Cutting back the plant in late winter or early spring before the new growth starts can also help keep it neat and tidy.
- When doing so, avoid cutting into the base of the plant, as it may damage the crown.
Landscaping Uses for Dianella tasmanica
Dianella tasmanica is a versatile plant that enhances a variety of landscape designs. It is commonly used as a groundcover, in shaded borders, or beneath large trees. Its compact growth habit, attractive foliage, and vibrant blue berries make it ideal for mass plantings, rockeries, and as a border plant near water features.
In addition to being visually appealing, the plant is drought-tolerant and frost-resistant, making it an excellent choice for sustainable and low-maintenance gardens.
Varieties
Named cultivars like ‘Little Devil’ are perfect for smaller spaces, while ‘Rainbow’ adds variegated foliage for visual interest. The ‘Tasred’ cultivar is known for its red-toned leaves in cooler months and its salt tolerance, making it ideal for coastal gardens or areas exposed to saline water.


