How to Grow Dianella
Wikimedia Commons
Dianella
Dianella tasmanica
grassDianella is a striking ornamental grass-like perennial native to Australia and Tasmania, known for its dramatic blue or purple berries and arching strappy foliage. The plant produces delicate blue or purple flowers in late spring to early summer, followed by colorful berry clusters that persist for months. It serves as an excellent structural element in gardens while also attracting birds and wildlife.
Looking for a specific variety?
When should you plant Dianella in your zone?
Get a personalized planting timeline — when to start seeds, transplant, and harvest — based on your USDA zone and local frost dates. Free to start.
Example Dianella timeline · Pittsburgh, PA (Zone 6b)
-
Plant Dianella
Around Apr 17Near Pittsburgh's average last spring frost.
-
Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
-
Harvest Dianella
Around Oct 14≈ 180 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Dianella dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 8-11, tolerating subtropical and warm temperate climates
Sign up free to see if Dianella grows in your zone — and get a personalized planting timeline.
Get my Dianella timeline →Growth Stages
Establishment
4-8 weeksYoung plants with emerging strappy foliage, often showing 4-6 leaves per shoot
Water regularly to keep soil consistently moist. Mulch around base. Avoid transplanting stress by planting in spring in cooler zones.
Vegetative Growth
6-12 monthsDense clumps of elongated, arching green or variegated foliage developing gradually taller and wider
Allow 6-12 months for plants to mature sufficiently to flower. Remove dead or damaged foliage. Minimal fertilizing needed; avoid nitrogen-rich feeds.
Flowering
4-8 weeksDelicate small flowers in blue, purple, or lavender tones appearing in clusters above foliage in late spring to early summer
Flowers emerge on erect or arching stems. Do not deadhead if berries are desired. Ensure adequate light for best bloom and berry set.
Fruiting & Berry Development
8-24 weeksBright blue, purple, or indigo berries developing from spent flowers, creating ornamental berry clusters that persist for 2-6 months
Berries are the main ornamental feature; refrain from cutting spent flowers. Berries attract birds and wildlife. Keep plant healthy to maximize berry production.
Dormancy/Maintenance
Variable by zoneIn cooler zones, foliage may pale or plants slow growth in winter; in warm zones, growth continues year-round
Trim dead foliage in spring after winter or once berries fall. No pruning required other than tidy-up. Divide overcrowded clumps every 3-4 years.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
-
and
Hand-pick, use beer traps, mulch barriers, or organic slug pellets. Less problematic in established plants.
-
Increase humidity with regular watering; use horticultural oil or neem oil spray if infestation occurs. Rare in outdoor settings.
-
Inspect plant regularly; treat with insecticidal soap or neem oil. Remove affected foliage if necessary.
-
Spray with neem oil or horticultural soap. Usually not a serious problem in well-ventilated outdoor gardens.
Uses
Landscape Structure & Interest
OrnamentalDianella provides year-round architectural interest with strappy foliage and stunning long-lasting blue or purple berries that add color to borders, containers, and mixed gardens. The upright yet arching form complements grasses, perennials, and shrubs in contemporary or cottage gardens. [source]
Bird & Pollinator Attraction
WildlifeThe abundant berries are highly attractive to native birds and wildlife, particularly in late summer and autumn when food sources are scarce. The flowers attract bees and other beneficial pollinators during the blooming season. [source]
Floral Arrangements & Cut Foliage
CraftDianella's arching foliage and long-lasting berries are prized by florists and gardeners for fresh and dried arrangements. The sturdy stems hold color well and add texture and movement to bouquets and displays. [source]
Container Growing
HouseholdDianella performs well in large containers or pots on patios, balconies, and courtyards, offering graceful form and colorful berries. Container-grown plants require more frequent watering and benefit from well-draining potting soil. [source]
Indigenous Food & Cosmetic Uses
CulinaryHistorically, Australian Aboriginal peoples harvested and consumed Dianella berries, which have mild nutritional value. The plant is also used in traditional herbal practices in some cultures, though not widely commercialized. [source]
Harvest Tips
Dianella is grown as an ornamental; berries are not harvested for consumption. Cut foliage and berry stems for arrangements in mid-summer to fall when berries are fully colored and firm. Harvest sparingly to maintain plant structure. Foliage can be cut anytime during growing season for floral arrangements.
Fun Facts
- 🌱 Dianella berries can remain on the plant for up to six months, providing extended visual interest and food for birds long into autumn and winter.
- 🌱 The plant is native to Australia and Tasmania, where it thrives in coastal and woodland environments; it is also found in similar climates across the Pacific region.
- 🌱 Dianella is often called 'Flax Lily' due to its flax-like strappy foliage, though it is not a true lily and is more closely related to the day-lily family.
Gardening Terms
New to gardening? Learn about terms used in this guide:
Join 30,000 gardeners planning their gardens with LizPlants.
Get your personalized Dianella planting timeline
Tell us your zip code and we'll calculate exactly when to start Dianella seeds, transplant seedlings, and harvest — based on your USDA zone and local frost dates. Includes calendar reminders and printable task lists. Free to start.
Get my Dianella timeline →