Photo: The original uploader was KarlM at English Wikipedia.CC BY-SA 2.5via Wikimedia Commonsresized / cropped
Kau Haleakala Silversword Plant Care
Argyroxiphium kauense (Rock & Neal) O.Deg. & I.Deg.
Updated · Sources · How we source care data
The Mauna Loa silversword, Argyroxiphium kauense, or Kaʻū silversword, is a rare species of flowering plant in the aster family. It is endemic to the eastern and southern slopes of Mauna Loa on the island of Hawaiʻi. A. kauense occurs in mountainous shrublands, bogs, and open mesic forest. The species is managed by the National Park Service and Hawaiʻi State Department of Forestry and Wildlife. It is a federally listed endangered species of the United States. There are three known populations remaining, for a total of fewer than 1000 individuals.
Every 7–14 days
Full sun to partial shade
50–80°F
40–70%
At a glance
How do you care for Kau Haleakala Silversword?
Water Kau Haleakala Silversword every 7–14 days, letting the top layer of soil dry out between waterings, and give it full sun to partial shade. It prefers temperatures of 50–80°F (10–27°C) and 40–70% humidity. Fertilize it every 6 months during the growing season.
What Is the Kau Haleakala Silversword?
Kau Haleakala Silversword (Argyroxiphium kauense) belongs to the Asteraceae family within the Argyroxiphium genus. Kau Haleakala Silversword is native to the eastern and southern slopes of Mauna Loa on the island of Hawaiʻi. Kau Haleakala Silversword is also known as Argyroxiphium sandwicense.
Kau Haleakala Silversword displays a rosette-forming perennial growth habit, reaching up to 3 ft tall with a spread of approximately 2 ft. Kau Haleakala Silversword produces bright yellow composite flowers in clusters.
Leaf size: approximately 12 inches.
How Often Should You Water a Kau Haleakala Silversword?
Argyroxiphium kauense 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 Kau Haleakala Silversword Need?
Kau Haleakala Silversword thrives in full sun to partial shade.
Light Requirement
Full sun to partial shade
What Temperature and Humidity Does the Kau Haleakala Silversword Prefer?
Argyroxiphium kauense grows best at temperatures of 50–80°F. Kau Haleakala Silversword prefers humidity levels of 40–70%.
Temperature
50–80°F
Humidity
40–70%
What Soil Mix Works Best for a Kau Haleakala Silversword?
Well-draining sandy soil with good aeration. Good drainage is essential for Kau Haleakala Silversword to prevent waterlogging, which leads to root rot and fungal issues.
How Often Should You Fertilize a Kau Haleakala Silversword?
Feed Kau Haleakala Silversword every 6 months during the growing season (spring and summer) with a balanced fertilizer diluted to the strength on the label.
Pause feeding in autumn and winter, when growth slows, and never fertilize dry soil — water first.
Fertilizing
Every 6 months
During the growing season
The PlantoScan app can remind you when to water and when to fertilize each plant.
How Do You Repot a Kau Haleakala Silversword?
Repot every 2-3 years in spring. 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 Kau Haleakala Silversword?
Kau Haleakala Silversword can be propagated through seeds, division of offsets. Similar propagation techniques also apply to occasional papers of bernice pauahi bishop museum of polynesian ethnology and natural history plant care, which shares the same genus.
Is the Kau Haleakala Silversword Toxic to Pets and Children?
Pet safety not verified
The ASPCA does not list Kau Haleakala Silversword, 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 Kau Haleakala Silversword?
Kau Haleakala Silversword is susceptible to aphids, spider mites, mealybugs. 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 Kau Haleakala Silversword Need?
Kau Haleakala Silversword grows outdoors in USDA Zone 12a. It survives winters down to planting zone 12a. Kau Haleakala Silversword is native to the eastern and southern slopes of Mauna Loa on the island of Hawaiʻi. In cooler regions, grow Kau Haleakala Silversword as a houseplant or bring it indoors before the first frost.
Hardiness Zone
Zone 12a
Keep exploring plants
Kau Haleakala Silversword 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 Argyroxiphium genus — compare its care with other Argyroxiphium species on PlantoScan.
Argyroxiphium is part of the Asteraceae plant family — browse all Asteraceae genera and species.
Kau Haleakala Silversword thrives in bright light and direct sun — see other bright-light plants.
More Argyroxiphium Species
Other Argyroxiphium species in PlantoScan's care catalogue share similar watering, light, and soil preferences:
Sources
- Scientific name & taxonomy: Argyroxiphium kauense (Rock & Neal) O.Deg. & I.Deg., family Asteraceae (first published in Fl. Hawaiiensis , Fam. 344: s.p. (1957)) — World Flora Online record, IPNI name record.
- Pet toxicity: Pet safety not verified: the ASPCA does not list Kau Haleakala Silversword, 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.
- Photo: The original uploader was KarlM at English Wikipedia., CC BY-SA 2.5, Wikimedia Commons — original.
- 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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