Soft Spear Grass Plant Care
Austrostipa mollis (R.Br.) S.W.L.Jacobs & J.Everett
Updated · Sources · How we source care data
Austrostipa mollis, also known as the soft speargrass or supple speargrass is a robust, erect tufted perennial speargrass in the Poaceae family. It is native to Australia, and found in Western Australia, South Australia, Victoria, ACT and Tasmania.
Every 7–14 days
Full sun
50–90°F
30–70%
At a glance
How do you care for Soft Spear Grass?
Water Soft Spear Grass every 7–14 days, letting the top layer of soil dry out between waterings, and give it full sun. It prefers temperatures of 50–90°F (10–32°C) and 30–70% humidity.
Where Is the Soft Spear Grass Native To?
What Is the Soft Spear Grass?
Soft Spear Grass (Austrostipa mollis) belongs to the Poaceae family within the Austrostipa genus. Soft Spear Grass is native to Australia, and found in Western Australia, South Australia, Victoria, ACT and Tasmania.
Soft Spear Grass displays a tall, clumping grass growth habit, reaching up to 5 ft tall with a spread of approximately 2 ft. Soft Spear Grass produces inconspicuous flowers on tall stalks.
Leaf size: approximately 12 inches.
How Often Should You Water a Soft Spear Grass?
Austrostipa mollis requires watering every 7–14 days. Allow the top layer of soil to dry between waterings to prevent root rot. Reduce watering frequency during winter when growth slows.
Watering Frequency
Every 7–14 days
Let soil partially dry between waterings
What Light Does the Soft Spear Grass Need?
Soft Spear Grass thrives in full sun.
Light Requirement
Full sun
What Temperature and Humidity Does the Soft Spear Grass Prefer?
Austrostipa mollis grows best at temperatures of 50–90°F. Soft Spear Grass prefers humidity levels of 30–70%.
Temperature
50–90°F
Humidity
30–70%
What Soil Mix Works Best for a Soft Spear Grass?
Well-draining sandy soil with good aeration. Good drainage is essential for Soft Spear Grass to prevent waterlogging, which leads to root rot and fungal issues.
How Do You Repot a Soft Spear Grass?
Divide clumps every 2-3 years. Choose a pot one size larger than the current container, and ensure it has drainage holes to allow excess water to escape.
How Do You Propagate a Soft Spear Grass?
Soft Spear Grass can be propagated through seeds. Similar propagation techniques also apply to knotty spear grass plant care, which shares the same genus.
Is the Soft Spear Grass Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Soft Spear Grass, so we can't confirm whether it is safe for cats and dogs. Keep pets from chewing it as a precaution.
This is a general caution, not veterinary or medical advice. If your pet ate a plant, contact your vet or animal poison control.
See all plants toxic to cats and plants toxic to dogs.
What Pests and Diseases Affect the Soft Spear Grass?
Soft Spear Grass is susceptible to grasshoppers, aphids. Inspect the foliage regularly, especially along leaf undersides and stems. Treat infestations promptly with insecticidal soap or neem oil to prevent spread.
Yellow leaves, brown tips or drooping? See common plant problems and how to fix them.
What USDA Hardiness Zone Does the Soft Spear Grass Need?
Soft Spear Grass grows outdoors in USDA Zone 12a. It survives winters down to planting zone 12a. Soft Spear Grass is native to Australia, and found in Western Australia, South Australia, Victoria, ACT and Tasmania. In cooler regions, grow Soft Spear Grass as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 12a
Keep exploring plants
Soft Spear Grass is one of many species covered in the complete plant care and identification guide, which groups plants by genus, attribute, and popularity.
It belongs to the Austrostipa genus — compare its care with other Austrostipa species on PlantoScan.
Austrostipa is part of the Poaceae plant family — browse all Poaceae genera and species.
Soft Spear Grass thrives in bright light and direct sun — see other bright-light plants.
More Austrostipa Species
Other Austrostipa species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
Sources
- Scientific name & taxonomy: Austrostipa mollis (R.Br.) S.W.L.Jacobs & J.Everett, family Poaceae (first published in Telopea 6: 587 (1996)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Soft Spear Grass, so we can't confirm whether it is safe for cats and dogs. Checked against the ASPCA plant list; any other toxicity note on this page comes from PlantoScan's plant database.
- Hardiness zone: USDA Zone 12a, calculated from the plant's minimum temperature.
- Care values(watering, light, temperature, humidity, soil, fertilizing): PlantoScan's plant database, filtered by automatic plausibility checks — values that fail them are hidden. How we source and check plant data.
Spotted a mistake? Email info@upvision.media with the page link — we check and correct reported errors.
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