Common Name Flax lily, Tasman flax lily
Botanical Name Dianella tasmanica
Family Asphodelaceae
Plant Type Perennial
Mature Size 1.5-2 ft. tall, 2.5-3 ft. wide
Sun Exposure Full, partial
Soil Type Sandy, loamy, well-drained
Soil pH Acidic, neutral
Bloom Time Spring
Flower Color Blue, white, purple
Hardiness Zones 9-11 (USDA)
Native Areas Australia, Asia

Flax Lily Care

Here are the most important care requirements if you want your flax lily to thrive:

  • Plant as a perennial outside in USDA Zones 9 to 11 or grow as a houseplant indoors or an annual outdoors in cooler climate zones.
  • Keep in full shade in hotter, sunnier zones and partial shade in cooler zones.
  • Until it is established, water a few times per week but make sure not to overwater.
  • Feed in spring with a fertilizer for acid-loving plants.
  • Only every five years, prune the plant back to the crown in the fall.

Light

Grow flax lily in full shade if you live in a region with very hot, dry summers. If your summers are warm to moderately hot, plant it in partial shade.

Soil

The soil should be well-draining. Though flax lily prefers sandy or loamy soil, it is adaptable enough to handle even poor soil with ease.

Water

Until the plant is established, water it just enough to keep the soil moderately moist. Flax lily tolerates drought well once it is mature. If the plant begins to droop or turn brown, cut back on the water.

Temperature and Humidity

When planted outdoors, flax lily needs hot, humid weather up to 95 degrees F to truly thrive. These temperatures are ideal; however, the plant is winter hardy enough to come back, year after year, even when winter temperatures dip to 20 degrees F.

When grown as a houseplant, it tolerates temperatures down to 65 to 70 degrees F, but don’t be surprised if it remains a foliage plant and doesn’t produce many blooms.

Fertilizer

Feed flax lily in spring before the appearance of new growth with a fertilizer for acid-loving plants, the same kind that you would use for azaleas.

Types of Flax Lily

Variety in the world of flax lilies comes mainly in the form of cultivars with variegated foliage:

  • ‘Variegata’: green leaves with white margins.
  • ‘Silver Streak’: green and white striped leaves.
  • ‘Yellow Stripe’: long, arched, green leaves with yellow stripes.

Pruning

Flax lily only needs major pruning only about once every five years to help ensure it continues to bloom and present lovely foliage. Prune the lilies back to the crown during the fall when the foliage has begun to turn brown.

Propagating Flax Lily

Flax lily slowly spreads in a clumping habit through rhizomes. Dividing the plant is the easiest way to propagate it.

  1. In the spring, carefully dig up the rhizomes with a shovel.
  2. Separate the rhizomes into clumps, breaking them apart cleanly with your fingers or using a sharp knife.
  3. Replant the divisions immediately at the same depth as the original plant and water them regularly until established,

Potting and Repotting Flax Lily

Flax lily does very well in containers. When initially potting flax lily, choose a pot that has excellent drainage and lets moisture evaporate. Terra-cotta works well. Good potting soil is plenty for flax lily to thrive, as long as it remains loose and well-drained.

Repot the lily to a larger pot when the rhizomes fill up the pot and the plant begins to show signs of struggle, such as browned or stunted leaves. Flax lily is also easy to divide if you prefer to keep it in the same pot with fresh potting soil.

Overwintering

Flax lily doesn’t need winter protection when grown in USDA Zones 9-11. Expect the foliage to die back in winter and spring back when the temperatures warm up.

Flax lily grown in a container is easy to overwinter, as you simply bring it indoors. Reduce the water during the dormancy period. Move the plant back outdoors when the temperatures have reached at least 70 degrees F.

Common Pests and Plant Diseases

Flax lily is susceptible to diseases such as leaf spot and powdery mildew. You can lower the chances of such infestations through generous spacing, by avoiding overhead watering, and by watering in the morning so that the soil has a chance to dry before night falls.

How to Get Flax Lily to Bloom

Flax lily is mostly grown as a foliage plant but it does produce enough blooms to be a focal point.

Bloom Months

Flax lily normally blooms in the summer months of June, July and August.

What Does Flax Lily’s Flowers Look and Smell Like?

The flowers bloom in panicles on stalks that jut up over the foliage. The individual blooms are small (12 inch to 34 inch across) but numerous enough to put on a show. They are usually blue (with striking yellow stamens) but occasionally white. The flowers are fragrant with a sweet, earthy scent and are succeeded by shiny, blue berries.

How to Encourage More Blooms

Flax lily thrives in higher temperatures and humidity and these conditions will encourage the most blooms.

Caring for Flax Lily After it Blooms

When finished blooming, for a tidier look, trim the flax lily back to remove any browning foliage.

Deadheading Flax Lily Flowers

Although the blooms will shed on their own, removing the spent flower heads as they begin to wither improves the flowering as it concentrates the nutrients in the other flowers.

Common Problems with Flax Lily

Flax lily plants are relatively tough, just keep an eye out for these two issues:

Rusty-Colored Leaves

This is a sign of a fungal infection or “rust”. Leaf rust appears as orange spots or stripes on the foliage. To remedy this, cut the plant down to about 6 inches above the ground and apply a copper-based fungicidal spray.

Drooping Foliage

Drooping or browning foliage is a sign that part of the soil is too soggy. Flax lilies require well-draining soil and don’t tolerate standing water.

FAQ


    • Flax lily loves dappled shade, so place it in an indoor area where it will receive indirect light.

    • Flax lily is botanically unrelated to flax seed, which comes from the flax plant, Linum usitatissimum, commonly known as flax or linseed. The flax plant is cultivated both for its nutritious seeds as well as for its fibers which are used to produce linen yarn and fabric. The flax lily, on the other hand, is a purely ornamental plant.